Disability and Health Journal 8 (2015) 424e433 www.disabilityandhealthjnl.com
Research Paper
Factors associated with psychotropic prescriptions, psychiatric hospitalization, and spending among Medicare beneficiaries under 65 Jingjing Qian, Ph.D.a,*, Saranrat Wittayanukorn, M.S.a, Grant McGuffey, Pharm.D.b, and Richard Hansen, Ph.D.a a
Department of Health Outcomes Research and Policy, Auburn University, Harrison School of Pharmacy, Auburn, AL 36849, USA b Palmetto Health Richland, Columbia, SC 29203, USA
Abstract Background: Medicare beneficiaries under 65 are a medically heterogenous population with significant psychiatric health service utilization. Patterns of psychiatric health services utilization and spending have not been well studied in this population. Objective: To estimate and compare annual trends in psychotropic prescriptions, psychiatric hospitalization, and total Medicare spending between Medicare beneficiaries !65 and those >65. We also identified factors associated with these outcomes among Medicare beneficiaries under 65. Methods: This serial cross-sectional study used 2006e2009 Medicare Current Beneficiary Survey (MCBS) data linked with Medicare claims. Psychotropic prescription and psychiatric hospitalization were measured using claims data. Total annual Medicare spending included reimbursements from Medicare Parts A, B, and D. Repeated person-year data were analyzed using generalized estimating equation (GEE) models to examine associations between factors and outcomes among beneficiaries !65, controlling for covariates. Results: Over one-third of beneficiaries !65 used at least one psychotropic prescription annually. Annual prevalence of psychotropic prescription and psychiatric hospitalization was higher among beneficiaries !65 than those >65 (threefold and ten-fold, respectively), as well as Medicare spending. The annual prevalence of psychiatric hospitalization decreased over time among beneficiaries !65. Antidepressants were the most prevalently prescribed psychotropic drug class among beneficiaries !65. Factors associated with psychiatric services utilization and spending among beneficiaries !65 included demographics and health insurance access, self-reported health, smoking status, and comorbidities (all P ! 0.05). Conclusions: Our findings highlight the special psychiatric health care needs of Medicare beneficiaries under 65 and call for the attention of policy makers and clinicians to this understudied population. Ó 2015 Elsevier Inc. All rights reserved. Keywords: Psychotropic prescription; Psychiatric hospitalization; Medicare; Spending; Disability
Individuals under age 65 become eligible for Medicare due to their permanent disabilities, including end-stage renal disease (ESRD). This group represented 17% of the Medicare population in 2012.1 Medicare beneficiaries under 65 are a medically heterogenous population and about one-third of them are disabled as a result of a mental disorder.2,3 Compared to beneficiaries aged 65 and older, beneficiaries under 65 have lower income and poorer access to affordable supplemental insurance coverage.3,4 A Funding/support: This work was supported by the American Association of Colleges of Pharmacy (AACP) New Investigator Award. The funding source had no role in the design and conduct of the study. Conflicts of interest: All authors have no conflict of interest to disclose. * Corresponding author. Department of Health Outcomes Research and Policy, Auburn University, Harrison School of Pharmacy, 038 James E. Foy Hall, Auburn, AL 36849-5506, USA. Tel.: þ1 334 844 5818; fax: þ1 334 844 8307. E-mail address: [email protected] (J. Qian). 1936-6574/$ - see front matter Ó 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.dhjo.2015.03.005
national Medicare beneficiary survey found the rates of failure to fill one or more prescriptions in 2004 were significantly higher among beneficiaries aged 18e64 years than those aged 65 and older, and higher among beneficiaries with psychiatric conditions than those without these conditions.5 Medicare beneficiaries under 65 are a special population that deserves policy consideration to ensure adequate and affordable health insurance coverage as well as quality health care, especially for psychiatric health services. Medicare beneficiaries under 65 have received little research attention compared to senior beneficiaries.3 Previous studies have shown that the presence of mental illness with or without other comorbid conditions increases health services utilization and spending of Medicare beneficiaries.6e8 But a majority of health services research related to chronic and psychiatric conditions among the Medicare population has been focusing on beneficiaries aged 65 and older.8e10 To our knowledge, no study has examined
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factors associated with psychiatric health services utilization and spending targeting beneficiaries under 65, the subgroup of Medicare beneficiaries with significantly higher cognate and behavioral disorders. Further, policy changes over the past decade may be important and have a unique impact on the Medicare population. In 2006, Medicare Part D was implemented to subsidize the cost of prescription drugs for all Medicare beneficiaries. Evidence has shown that the implementation of Medicare Part D is associated with improvements in antidepressant use and adherence in depressed beneficiaries who were aged 65 and older and previously lacked drug coverage.11 Yet, little is known about the trends in psychiatric services utilization and spending after the implementation of Medicare Part D, especially among beneficiaries under 65. Up-to-date national estimates of and trends in psychiatric services utilization and spending after Medicare Part D could guide and promote improvement in access strategies and payment policies for this population. In addition, understanding factors impacting service utilization and spending among Medicare beneficiaries under 65 is important for policy makers and practitioners to identify young and disabled beneficiaries with high-risk and highspending so that early interventions and innovative payment and service delivery models could be tailored for this vulnerable population. In order to fill this important knowledge gap regarding trends in psychiatric services utilization and psychotropic medication use among Medicare population under 65, this study estimated and compare annual trends in any psychotropic prescription utilization, psychiatric hospitalization, and total annual Medicare spending between Medicare beneficiaries under 65 and those 65 years and older. We also identified factors associated with any psychotropic prescription utilization, psychiatric hospitalization, and spending among Medicare beneficiaries under 65.
Methods Study population and sample This serial cross-sectional study used 2006e2009 Medicare Current Beneficiary Survey (MCBS) Cost and Use data files. The MCBS is a continuous, multipurpose survey of a nationally representative sample of about 12,000 Medicare beneficiaries of all ages annually. The MCBS Cost and Use files link self-reported survey with Medicare claims to provide complete expenditure data on all received health care services. Thus, the files can support a broader range of research and policy analyses on the Medicare population than using either survey data or administrative claims data alone.12 Survey-reported data include information on the use and cost of all types of medical services, health insurance, education, income, health status, and physical functioning. Medicare claims data includes health services
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utilization and cost information on inpatient, outpatient services, and prescription drugs.12 We included nationally representative Medicare community-dwelling beneficiaries who completed the survey in 2006e2009. Beneficiaries enrolled in Medicare health maintenance organizations (HMOs) in any given year were excluded (about 22%e38% of sample, depending on year) due to their lack of complete Medicare Parts A and B claims data. The final study sample included a total of 13,971 individual beneficiaries of all ages in the 4-year study period. We included beneficiaries >65 for the purpose of comparing annual trends of psychiatric services utilization and spending with younger beneficiaries. The annual sample varied between 1048 (2009, weighted n 5 3.7 million) and 1341 (2006, weighted n 5 3.9 million) individuals for beneficiaries under 65 and between 4459 (2009, weighted n 5 18.6 million) and 5886 (2006, weighted n 5 21.1 million) individuals for beneficiaries >65. This study was determined to be exempt human subjects research by the Auburn University institutional review board (IRB). Outcomes measurements Outcome measures included any psychotropic prescription utilization (overall and by drug class), any psychiatric hospitalization, and annual total Medicare spending in 2006e2009. Any psychotropic prescription utilization was defined as having one or more antidepressants (e.g., selective serotonin reuptake inhibitors and serotoninnorepinephrine reuptake inhibitors), antipsychotics (e.g., typical and atypical antipsychotics), stimulants (e.g., dextroamphetamine and methylphenidate), mood stabilizers (e.g., lamotrigine and carbamazepine), anxiolytics (e.g., benzodiazepines), hypnotics (e.g., temazepam and phenobarbital), or antimanic drugs (e.g., lithium) captured in Medicare prescription claims data. Any psychiatric hospitalization included any inpatient hospital stay with a primary admission diagnosis of depression, anxiety, bipolar disorder, alcohol or drug abuse, schizophrenia and other psychotic disorders in Medicare inpatient hospital claims data. These psychiatric disorders were defined using the algorithms and International Classification of Diseases, ninth revision (ICD-9-CM) diagnosis codes developed by the Centers for Medicare & Medicaid Services (CMS) Chronic Condition Warehouse.13 Annual total Medicare spending included all beneficiary-level expenditures reimbursed through Medicare Parts A, B, and D during each calendar year. Part A reimbursements included Medicare payment for hospital care, skilled nursing facility care, hospice, and home health services. Part B reimbursements included Medicare payment for outpatient care, physician office visits, and durable medical equipment. Part D reimbursements included amount paid by Medicare for any prescription claims. To ensure comparability of Medicare spending results over
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the 4-year study period, all spending amounts were inflated to constant 2009 US dollars using the urban Medical Component of the Consumer Price Index.14 Factors associated with outcomes In order to identify factors associated with any psychotropic prescription utilization, any psychiatric hospitalization, and total annual Medicare spending among beneficiaries under 65, the following factors were assessed: demographic characteristics, socioeconomic factors, health insurance benefit variables, self-reported health and smoking status, and comorbidity. Demographic characteristics included age (0e44 and 45e64), gender (male and female), race/ethnicity (white, black, Hispanic, and other), and region (Northeast, Midwest, South, and West). Socioeconomic factors included marital status (married, widowed, divorced, and other) and self-reported education (no or some high school, high school graduate, and some college or more). Additionally, two binary health insurance benefit variables (low-income subsidy and Medicare-Medicaid dual eligibility) were also identified. Since Medicare provides premium subsidies for low-income beneficiaries who enrolled in Medicare Part D prescription plans (PDP), we defined a beneficiary’s low-income subsidy status as ‘‘yes’’ if he/she received any premium subsidies in any month of a year. Medicare-Medicaid dual eligibility was defined as ‘‘yes’’ if a beneficiary was enrolled in Medicaid at least one month of a year. Further, self-reported health status (excellent or good, fair, and poor), self-reported current smoking status (yes and no), and count of chronic comorbidities were also assessed. In the MCBS Cost and Use Health Status & Functioning (community) survey, beneficiaries were asked about their ‘‘general health compared to others at the same age’’ and if they ‘‘smoke now.’’ We used these two questions to define beneficiary’s self-reported health status and current smoking status. We also identified a total of 11 prevalent chronic comorbidities in the Medicare population using the algorithms and ICD-9-CM diagnosis codes developed by the CMS Chronic Condition Warehouse in the linked Medicare claims data.13 These comorbidities included acute myocardial infarction, asthma, chronic obstructive pulmonary disease, chronic kidney disease, diabetes, heart failure, hyperlipidemia, hypertension, ischemic heart disease, stroke, and osteoporosis. We then counted the comorbidities they had in any given year and further categorized as 0, 1, 2, and 3 or more chronic comorbidities. Statistical analysis Annual prevalence and mean trends of any psychotropic prescription utilization and psychiatric hospitalization, as well as trends of annual mean total Medicare spending per beneficiary were estimated for each calendar year for
beneficiaries !65 and those >65. Trends of annual mean total Medicare spending, and by subcategory (i.e., Medicare Parts A, B, and D) per beneficiary were estimated across years. Linear regression models were used to test for trends in the annual prevalence, means, and spending over time for both age groups. In addition, we combined beneficiaries !65 and those >65 in linear regression models and compared their outcome estimates by testing the dummy variable of age group. We also pulled all psychotropic prescription utilization by therapeutic class over the 4 years and estimated proportion of individual therapeutic classes for beneficiaries !65 and those >65. To identify factors associated with having any psychotropic prescription utilization (overall and by drug class), psychiatric hospitalization, and annual total Medicare spending among beneficiaries under 65, a total of 4864 person-years were derived from the 4-year data for bivariable and multivariable analyses. The bivariable analyses (Chisquare) compared factors between beneficiaries with and without any psychotropic prescription utilization and psychiatric hospitalization. Since an individual beneficiary could contribute up to three person-years of observations in the MCBS data, seven multivariable models with generalized estimating equations (GEE) were used to examine the conditional effects of factors on outcomes. GEE models are particularly useful for modeling clustered/correlated data (e.g., repeated observations among subjects) to achieve efficient parameter estimations and accurate standard errors (SEs).15 The first GEE model (Model 1) examined the associations between factors and any use of psychotropic prescription. GEE models 2e5 examined the associations between factors and any use of antidepressants, antipsychotics, mood stabilizers, and other psychotropic prescription (defined as combined use of hypnotics, antimanics, anxiolytics, and stimulants due to small proportions), respectively. Further, another GEE model (Model 6) was used to identify factors associated with any psychiatric hospitalization. In this model, two factors were re-categorized (i.e., race/ethnicity and marital status) due to small cell sizes (unweighted n ! 20) to maintain the stability of multivariable models.16 Models 1e6 used modified Poisson regression and a log link function to estimate prevalence ratios (PRs) with associated 95% confidence intervals (CIs). The last GEE model (Model 7) included two additional binary independent variables (any use of psychotropic prescription and psychiatric hospitalization) to predict annual total Medicare spending among those beneficiaries under 65 with any positive Medicare spending in 2006e2009 (n 5 4189 person years). In this modified generalized linear model (GLM) with GEE approach, a gamma distribution and log link function were used to handle the highly right-skewed health care spending data.17 To facilitate interpretation, the coefficients from Model 7 examining factors associated with higher annual total Medicare spending were converted to a marginal mean difference (MDD) with 95% CIs to show the magnitude of spending
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associated with specific factors after controlling for all other factors. In all multivariable models, the factor ‘‘low-income subsidy’’ was removed to avoid multicollinearity due to the substantial overlap with MedicareMedicaid dual eligibility. Results from all trend analyses, bivariable analyses, and multivariable models were weighted using the cross-sectional sampling weights provided in the MCBS data files to generate nationally representative estimates. All analyses were performed using SAS 9.2 (SAS Institute, Inc., Cary, NC). Statistical significance was set at P ! 0.05.
Results Results from trend analyses Over one-third (38.4%) of Medicare beneficiaries under 65 filled at least one psychotropic prescription annually. The annual prevalence of any psychotropic prescription utilization among beneficiaries under 65 increased from 34.8% in 2006 to 40.1% in 2009, compared with 12.4% e14.0% for those 65 years and older (Fig. 1, Panel a). The prevalence of psychotropic prescription was significantly higher in beneficiaries under 65 than those 65 and older (P ! 0.0001). But neither trend in prevalence of psychotropic prescription exhibited statistical significance over time in younger or aged beneficiaries (P 5 0.13 and P 5 0.20, respectively). The annual means of any psychotropic prescription utilization per beneficiary for beneficiaries under 65 was 9.9 (standard error (SE) 5 0.92) in 2006 and 9.4 (SE 5 0.30) in 2009 compared to 5.4 (SE 5 0.37) in 2006 and 6.1 (SE 5 0.17) in 2009 for older beneficiaries (Fig. 1, Panel b). Similarly, the mean number of psychotropic prescriptions was significantly higher in beneficiaries under 65 than those 65 and older (P ! 0.001). But neither trend in means of psychotropic prescription showed statistical significance over time in younger or aged beneficiaries (P 5 0.43 and P 5 0.20, respectively).
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The annual prevalence of any psychiatric hospitalization among beneficiaries under 65 was ten-fold higher than those 65 years and older. The prevalence decreased from 2.6% in 2006 to 1.9% in 2009 for beneficiaries under 65, compared with 0.2% in 2006 to 0.3% in 2009 for those >65 (Fig. 1, Panel a). The comparison in prevalence estimates of psychiatric hospitalization showed that beneficiaries under 65 had a higher prevalence than those 65 and older (P ! 0.0001). Trend analysis also confirmed the decreased trend in psychiatric hospitalization among beneficiaries under 65 (borderline P 5 0.05) and increased trend in psychiatric hospitalization among older beneficiaries (P 5 0.02). The annual means of any psychiatric hospitalization per beneficiary were similar and remained stable across year for both groups, accounting for approximately one hospitalization per beneficiary per year (Fig. 1, Panel b). For beneficiaries under 65, the most commonly prescribed psychotropic drug classes were antidepressants (28.7%), antipsychotics (14.1%), and mood stabilizers (9.6%), followed by hypnotics (8.8%) and anxiolytics (5.2%). Stimulants and antimanics were the least prescribed psychotropic drug classes among beneficiaries under 65, with annual prevalence around 1% (Fig. 2). For beneficiaries >65, the most prevalently prescribed psychotropic drug classes were antidepressants (9.8%), hypnotics (3.4%), antipsychotics (1.9%), and anxiolytics (1.8%). Mood stabilizers, stimulants, and antimanics were the least prescribed psychotropic drug classes among beneficiaries >65 with annual prevalence less than 1%. The annual total Medicare spending per beneficiary increased across years for both groups e from $9695 (SE 5 $727) in 2006 to $11,391 (SE 5 $729) in 2009 for beneficiaries under 65, compared with $8820 (SE 5 $207) to $9357 (SE 5 $318) for beneficiaries >65. Beneficiaries under 65 had lower annual Part A spending (P 5 0.04), similar annual Part B spending (P 5 0.24), and much higher annual total and Part D spending compared with those 65 years and older (both P ! 0.01) (Fig. 3). Although trend analysis in annual total
Fig. 1. Trends in prevalence and means of psychotropic prescription and psychiatric hospitalization among Medicare beneficiaries in 2006e2009 (weighted).
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Fig. 2. Weighted total proportions of psychotropic prescription utilization by therapeutic class among Medicare beneficiaries in 2006e2009.
or Part A Medicare spending per beneficiary did not exhibit statistical significance over time in either age group, aged beneficiaries had increased annual Part B and Part D over time (P 5 0.01 and P 5 0.03, respectively). Beneficiaries under 65 also had increased annual Part B spending over time (P 5 0.04), but the trend in Part D spending did not show statistical significance (P 5 0.33). Results from bivariable and multivariable analyses Among all beneficiaries under 65, bivariable analyses found that age, sex, marital status, education, health insurance benefits, self-reported health and current smoking statuses, counts of chronic comorbidities, and time (in year) were statistically different between psychotropic prescription users and non-users (all P ! 0.05). Age, health insurance benefits, and self-reported current smoking status were statistically different between those with and without any psychiatric hospitalization (all P ! 0.05, Table 1). After controlling for all other factors, multivariable results found that the prevalence of any psychotropic prescription utilization was higher in beneficiaries under 65 with younger age (0e44), female sex, white race (vs. black), being divorced, with no or some high school education (vs. those with some college or more), being MedicareMedicaid dual eligible, with poorer health status and currently smoking, and having 1 or more chronic comorbidities (all P ! 0.05, Table 2). In models examining factors associated with different psychotropic drug classes, younger age, certain marital status, and being MedicareMedicaid dual eligible were associated with higher likelihood of use of any antidepressants, antipsychotics, mood stabilizers, and other psychotropic drug classes. Female sex also was associated with higher use of different
psychotropic drug classes except for antipsychotics. White race/ethnicity was associated with higher use of antidepressants and mood stabilizers compared with blacks. Poorer health status was associated with higher use of antidepressants and other psychotropic drug classes except for antipsychotics and mood stabilizers. Concurrent smoking was associated with higher use of antidepressants and antipsychotics. Having more comorbidities was associated with different psychotropic drug classes except for mood stabilizers (all P ! 0.05, data not shown). Multivariable results found that the prevalence of any psychiatric hospitalization was higher in beneficiaries under 65 with younger age (0e44), being MedicareMedicaid dual eligible, currently smoking, and having 2 (compared to zero) chronic comorbidities (all P ! 0.05, Table 2). We also found that beneficiaries under 65 with any use of psychotropic prescriptions had an average of $5620 (95% CI 5 $3,825, $7700) more annual Medicare spending compared to those without. Those with any psychiatric hospitalization had an average of $12,531 (95% CI 5 $7,865, $18,466) more annual Medicare spending compared to those without. In addition, for beneficiaries under 65 who were younger in age, African American (vs. white), with higher education, Medicare-Medicaid dual eligible, with poorer health status and more chronic comorbidities also had higher annual total Medicare spending (all P ! 0.05, Table 2).
Discussion This study fills an important knowledge gap in psychiatric health services utilization and spending among Medicare beneficiaries under 65 e those with physical or
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Fig. 3. Trends in annual mean Medicare spending (total and by category) among Medicare beneficiaries in 2006e2009 (weighted).
mental disabilities. Our findings not only highlight the special health care needs of Medicare beneficiaries under 65, but also draw policy and practice attention to ensuring adequate and affordable health insurance coverage as well as high quality psychiatric health services for this vulnerable population. We found that the annual prevalence of any psychotropic prescription or psychiatric hospitalization was much higher among disabled beneficiaries under 65 compared to older beneficiaries, with a threefold higher prevalence of any psychotropic prescription and a ten-fold higher prevalence of psychiatric hospitalization, respectively. Although our trend analyses did not show the increased trends in annual prevalence of psychotropic prescription over time for either age group after the implementation of Medicare Part D, we found an increased trend in the prevalence of psychiatric hospitalization among older beneficiaries but a decreased trend in the prevalence of psychiatric hospitalization among beneficiaries under 65 during the same time period. We also found that total annual Medicare costs were approximately $2000 more for a beneficiary under 65 compared to a beneficiary >65. Our results demonstrated that aged beneficiaries had increased trend in annual Part B and Part D spending in 2006e2009. Beneficiaries under 65 also had an increased trend in annual Part B spending over time but not in Part D spending. Independent of demographic and socioeconomic factors, health status, and comorbidities, we found that being dually eligible for Medicare and Medicaid was associated with
higher likelihood of any psychotropic prescription utilization, overall and by drug class, among Medicare beneficiaries under 65. Beneficiaries who were MedicareMedicaid eligible had more than a twofold higher likelihood of any psychotropic prescription compared to those who were not eligible. Our results are consistent with Stuart et al18 and suggest that the Medicare low-income subsidy (99.8% of beneficiaries under 65 also received lowincome subsidy in this sample, which was weighted for 59.1% of beneficiaries under 65 nationwide) and Part D might provide meaningful assistance in removing costrelated barriers to medication use and increase access to medications for qualified beneficiaries. Our model also identified factors associated with psychiatric hospitalization among beneficiaries under 65. We found that younger age, being dual eligible for Medicare and Medicaid, currently smoking, and having 2 chronic comorbidities were associated with higher likelihood of psychiatric hospitalization. Specifically, younger (age 0e44) beneficiaries and those eligible for both Medicare and Medicaid had more than a twofold higher likelihood of psychiatric hospitalization than older (age 45e64) beneficiaries and those not dual eligible. Future research is needed to confirm these findings so that practitioners and policy makers might consider these patient subgroups as high priority for outpatient case management in an effort to minimize hospitalization risk and improve clinical outcomes for these patients.
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Table 1 Characteristics of the sample of Medicare beneficiaries under 65 (weighted n 5 15,145,931 person-years) Any use of psychotropic prescription Any use of psychiatric hospitalization Users
Nonusers
Users Pa
Characteristics
Weighted %
Person-years Demographics Age (year) 0e44 45e64 Sex Female Male Race/ethnicityb White Black Hispanic Other Region Northeast Midwest South West Socioeconomic factors Marital status Married Widowed Divorced Otherc Education No or some high school High school graduate Some college or more Health insurance benefit Low-income subsidy Medicare-Medicaid dual eligibility Self-report health status Excellent or good Fair Poor Self-report current smoking status Smoking now Count of chronic comorbidities 0 1 2 3 and more Year 2006 2007 2008 2009
38.4
61.6
31.2 68.8
21.6 78.4
57.5 42.5
39.3 60.7
75.3 17.1 3.2 4.4
71.2 21.4 3.2 4.2
20.5 21.6 44.1 13.8
18.0 22.1 45.0 14.9
20.8 7.5 29.9 41.8
40.9 6.6 22.5 30.0
35.8 35.1 29.2
30.3 31.5 38.2
86.3 70.6
42.1 32.6
40.0 33.4 26.5
46.4 34.4 19.2
44.9
32.6
33.6 25.1 16.6 24.7
50.0 16.9 13.9 19.2
22.7 25.3 26.7 25.3
26.7 25.7 23.8 23.7
Nonusers Pa
Weighted % 2.3
97.7
48.1 51.9
24.8 75.2
46.0 54.0
46.3 53.7
74.2 19.6 4.8 1.4
72.7 19.8 3.1 4.4
23.0 25.9 38.1 13.0
18.9 21.8 44.8 14.5
15.4 0 26.1 58.5
33.6 7.1 25.3 34.0
34.3 31.8 33.9
32.4 32.9 34.8
84.7 74.3
58.5 46.6
44.8 34.9 20.2
43.9 34.0 22.1
63.3
36.7
39.7 19.3 20.8 20.3
43.8 20.1 14.8 21.3
27.7 29.2 23.2 19.9
25.1 25.5 25.0 24.4
!0.01
!0.01
!0.01
0.95
0.20
0.06
0.66
0.62
!0.01
N/A
!0.01
!0.01 !0.01 !0.01
!0.01 !0.01
0.95
0.02
!0.01 !0.01 0.89
!0.01 0.51
0.64
N/A: not applicable. a Chi-square tests. b We used the race code in the MCBS Cost and Use Administrative Identification file to determine race/ethnicity category. The original race code includes white, black, Hispanic, Asian, North American Native, other, and unknown. We merged Asian, North American Native, other, and unknown into a new ‘‘Other’’ category in this study. c Including separated, never married, refused, and don’t know.
We found that Medicare spent much more for beneficiaries under 65 with psychiatric-related health care services than those without such services. For example, our results indicate that having any psychotropic prescription
and psychiatric hospitalization was associated with a $5620 and $12,531 higher annual Medicare spending per beneficiary under 65, respectively, after controlling for all other factors. According to a 2004 Agency for Healthcare
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Table 2 Associations between factors with use of psychotropic prescription, psychiatric hospitalization, and annual total Medicare spending among Medicare beneficiaries under 65 Any psychotropic prescriptiona Any psychiatric hospitalizationa Annual mean total Medicare spendingb Factors
PR
95% CI
PR
95% CI
MMD
95% CI
Any use of psychotropic prescription Any psychiatric hospitalization Demographics Age (year) 0e44 45e64 Sex Female Male Race/ethnicityc White Black Hispanic Other Non-whited Region Northeast Midwest South West Socioeconomic factors Marital status Married Widowed Divorced Otherf Widowed or divorcedg Education No or some high school High school Some college or more Medicare-Medicaid dual eligibility Self-report health status Excellent or good Fair Poor Self-report current smoking status Smoking now (vs. Never smoke/ previous smoke) Count of chronic comorbidities 0 1 2 3 and more
N/A N/A
N/A N/A
N/A N/A
N/A N/A
$5620e $12,531e
$3825, $7700e $7865, $18,466e
Reference 0.87e 0.80e0.95e
Reference 0.45e
0.27e0.75e
Reference $1512e
$2794, $23e
Reference 0.69e 0.61e0.77e
Reference 0.96
0.58e1.59
Reference $549
$742, $2036
Reference 0.67e0.91e 0.78e 0.93 0.67e1.28 0.99 0.76e1.29 N/A N/A
Reference N/A N/A N/A 0.81
N/A N/A N/A 0.48e1.37
Reference $2409e $1794 $1177 N/A
$342, $4927e $1003, $5553 $3137, $1424 N/A
Reference 0.91 0.78e1.08 0.92 0.79e1.07 0.89 0.74e1.08
Reference 0.86 0.77 0.68
0.45e1.63 0.42e1.42 0.31e1.51
Reference $176 $980 $79
$1946, $2858 $2722, $1180 $2070, $2814
Reference 1.20 0.99e1.46 1.31e 1.13e1.52e e 1.30 1.13e1.50e N/A N/A
Reference N/A N/A 2.07e 1.25
N/A N/A 1.07e4.02e 0.63e2.50
Reference $1437 $1796 $2002 N/A
$696, $4167 $11, $3994 $88, $4585 N/A
Reference 1.01 0.89e1.14 0.87e 0.75e1.00e e 2.04 1.77e2.36e
Reference 1.08 1.29 2.21e
0.61e1.90 0.77e2.19 1.26e3.88e
Reference $2215e $2022e $1837e
$416, $4390e $297, $4096e $45, $4000e
Reference 1.06e 1.00e1.13e e 1.12 1.04e1.21e
Reference 1.08 0.93
0.69e1.70 0.58e1.50
Reference $1511e $4350e
$308, $2884e $2627, $6348e
1.16e
2.57e
1.71e3.84e
$1042
$2349, $487
Reference 1.26 1.80e 1.59
0.82e1.96 1.14e2.87e 0.90e2.79
Reference $2695e $6096e $18,036e
1.07e1.27e
Reference 1.10e 1.02e1.20e 1.15e 1.05e1.26e e 1.20 1.10e1.31e
$1537, $4053e $3899, $8823e $14,050, $22,846e
PR: prevalence ratio; CL: confidence interval; MMD: marginal mean difference; N/A: not applicable. a Generalized estimating equations (GEE) multivariable models were performed to examine the conditional effects of identified factors on psychotropic prescription use and any psychiatric hospitalization. Results were weighted using MCBS averaged weights. Weighted n 5 15,145,931 person-years. b GEE multivariable model was performed to examine the marginal effects of identified factors on annual Medicare spending among those who had any Medicare spending during each year. Results were weighted using MCBS averaged weights. All spending were converted to 2009 US dollars. Weighted n 5 12,858,122 person-years. c We used the race code in the MCBS Cost and Use Administrative Identification file to determine race/ethnicity category. The original race code includes white, black, Hispanic, Asian, North American Native, other, and unknown. We merged Asian, North American Native, other, and unknown into a new ‘‘Other’’ category in this study. d Including African American, Hispanic, and other. This racial category was only appeared in the GEE model examining factors associated with any psychiatric hospitalization. e Statistically significant at P ! 0.05. f Including separated, never married, refused, and don’t know. g Including those who were either widowed or divorced. This marital status category was only appeared in the GEE model examining factors associated with any psychiatric hospitalization.
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Research and Quality (AHRQ) analysis, 22% of total hospital costs were attributable to adults with mental or substance use disorder and hospital stays involving these disorders were 29% longer than stays for other conditions.19 Our results may help policy makers identify potential disparities in Medicare spending: the substantial Medicare spending associated with factors such as race/ ethnicity, education, Medicare-Medicaid dual eligibility, health status, and count of chronic comorbidities may help policy makers shape quality improvement and cost containment efforts around these areas. Our findings highlight the need for providing adequate and affordable health insurance coverage of psychiatric health services for beneficiaries under 65. Indeed, over one-third of these young and disabled beneficiaries filled at least one psychotropic prescription annually, which makes them more sensitive to prescription formulary changes related to psychiatric drugs under Medicare Part D. In January 2014, CMS proposed to revise prior policy that required Part D plans to include on their formularies ‘‘all or substantially all’’ drugs including antidepressants and antipsychotics. The agency planned to exclude antidepressants, and potentially antipsychotics, from this ‘‘six protected classes’’ policy. This and similar proposals, if approved, will lead to a reduction in the numbers of medications available on Part D plan formularies for all Medicare beneficiaries. This has a possibility for unintended consequences. For example, the Oregon state Medicaid cutbacks on individuals with schizophrenia in 2003 were associated with increased state psychiatric hospitalization utilization among those who lost Medicaid coverage.20 Providing the needed psychiatric services would generate cost savings if patients adhere to treatment, avoid hospitalization, and have less use of costly services. Thus, policy makers should pay attention to health policy changes related to psychiatric services that could impact Medicare beneficiaries under 65 and ensure adequate prescription coverage for this vulnerable population. More work is needed to assess these implications at the drug level or among more narrowly defined subgroups. This study has several limitations. The cross-sectional study design only examined association instead of causality. Using diagnosis codes to ascertain psychiatric hospitalization and comorbidities could lead to disease misclassification. Further, our estimate of health services utilization and spending could only capture services paid by Medicare and missed those financed through other sources such as Medicaid or private insurance. The comparison between young and older Medicare beneficiaries could be influenced by differential survivorship, which might lead to underestimation of psychiatric service utilization and spending among beneficiaries 65 years and older. In addition, the self-reported variables identified from the MCBS data might introduce self-report bias. Beneficiaries enrolled in Medicare due to ESRD might present different health care utilization and spending from other beneficiaries under
65. Our data had limited statistical power to estimate such potential differences because of the low representative sample of ESRD enrollees (!2.0%) among beneficiaries under 65. Finally, results from this study may not be generalizable to Medicare beneficiaries enrolled in HMOs.
Conclusions In conclusion, this study fills important knowledge gaps of psychiatric health services utilization and spending among Medicare beneficiaries under 65. Findings highlight the special health care needs of young and disabled Medicare beneficiaries and identify certain factors impacting their likelihood of psychiatric services utilization and spending. Future research should dig deeper into understanding access to and quality of psychiatric services and utilization for this understudied population. References 1. Merrick EL, Perloff J, Tompkins CP. Emergency department utilization patterns for Medicare beneficiaries with serious mental disorders. Psychiatr Serv. Jun 2010;61(6):628e631. 2. Social Security Administration. Annual Statistical Report on the Social Security Disability Insurance Program, 2007. SSA Publication No.13e11826. Released August 2008. Available at: http://www.ssa.gov/ policy/docs/statcomps/di_asr/2007/di_asr07.pdf; Accessed 08.08.12. 3. Kennedy J, Tuleu IB. Working age Medicare beneficiaries with disabilities: population characteristics and policy considerations. J Health Hum Serv Adm. Winter 2007;30(3):268e291. 4. Cubanski J, Neuman P. Medicare doesn’t work as well for younger, disabled beneficiaries as it does for older enrollees. Health Aff (Millwood). Sep 2010;29(9):1725e1733. 5. Kennedy J, Tuleu I, Mackay K. Unfilled prescriptions of Medicare beneficiaries: prevalence, reasons, and types of medicines prescribed. Journal of managed care pharmacy. JMCP. JuleAug 2008;14(6): 553e560. 6. Dobrez D, Heinemann AW, Deutsch A, Durkin EM, Almagor O. Impact of mental disorders on cost and reimbursement for patients in inpatient rehabilitation facilities. Arch Phys Med Rehabil. Feb 2010;91(2):184e188. 7. Unutzer J, Schoenbaum M, Katon WJ, et al. Healthcare costs associated with depression in medically ill fee-for-service medicare participants. J Am Geriatr Soc. Mar 2009;57(3):506e510. 8. Himelhoch S, Weller WE, Wu AW, Anderson GF, Cooper LA. Chronic medical illness, depression, and use of acute medical services among Medicare beneficiaries. Med Care. Jun 2004;42(6):512e521. 9. Prince JD, Akincigil A, Kalay E, et al. Psychiatric rehospitalization among elderly persons in the United States. Psychiatr Serv. Sep 2008;59(9):1038e1045. 10. Huang H, Chan YF, Bauer AM, et al. Specialty behavioral health service use among chronically ill Medicare advantage patients with substance use problems. Psychosomatics. NoveDec 2013;54(6): 546e551. 11. Donohue JM, Zhang Y, Aiju M, et al. Impact of Medicare Part D on antidepressant treatment, medication choice, and adherence among older adults with depression. Am J Geriatr Psychiatry. Dec 2011;19(12):989e997. 12. Centers for Medicare & Medicaid Services: Medicare Current Beneficiary Survey (MCBS). Available at: https://www.cms.gov/ResearchStatistics-Data-and-Systems/Research/MCBS/index.html?redirect5/M CBS/; Accessed 03.04.13.
J. Qian et al. / Disability and Health Journal 8 (2015) 424e433 13. National CMS Medicare and Medicaid Research Data. Chronic Conditions Data Warehouse Chronic Condition Categories. Available at: https://www.ccwdata.org/web/guest/condition-categories; 2012. Accessed 16.04.13. 14. Bureau of Labor Statistics. Consumer Price Index. http://www.bls.gov/ cpi/#data; Accessed 02.05.13. 15. Hanley JA, Negassa A, Edwardes MD, Forrester JE. Statistical analysis of correlated data using generalized estimating equations: an orientation. Am J Epidemiol. Feb 15 2003;157(4): 364e375. 16. Peduzzi P, Concato J, Kemper E, Holford TR, Feinstein AR. A simulation study of the number of events per variable in logistic regression analysis. J Clin Epidemiol. Dec 1996;49(12):1373e1379.
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17. Barber J, Thompson S. Multiple regression of cost data: use of generalised linear models. J Health Serv Res Policy. Oct 2004;9(4): 197e204. 18. Stuart B, Yin X, Davidoff A, et al. Impact of Part D low-income subsidies on medication patterns for Medicare beneficiaries with diabetes. Med Care. Nov 2012;50(11):913e919. 19. Owens P, Myers M, Elixhauser A, Brach C. Care of Adults With Mental Health and Substance Abuse Disorders in US Community Hospitals, 2004eHCUP Fact Book No. 10. Rockville, MD: Agency for Healthcare Research and Quality; 2004. 20. McFarland BH, Collins JC. Medicaid cutbacks and state psychiatric hospitalization of patients with schizophrenia. Psychiatr Serv. Aug 2011;62(8):871e877.
Research Paper
Factors associated with psychotropic prescriptions, psychiatric hospitalization, and spending among Medicare beneficiaries under 65 Jingjing Qian, Ph.D.a,*, Saranrat Wittayanukorn, M.S.a, Grant McGuffey, Pharm.D.b, and Richard Hansen, Ph.D.a a
Department of Health Outcomes Research and Policy, Auburn University, Harrison School of Pharmacy, Auburn, AL 36849, USA b Palmetto Health Richland, Columbia, SC 29203, USA
Abstract Background: Medicare beneficiaries under 65 are a medically heterogenous population with significant psychiatric health service utilization. Patterns of psychiatric health services utilization and spending have not been well studied in this population. Objective: To estimate and compare annual trends in psychotropic prescriptions, psychiatric hospitalization, and total Medicare spending between Medicare beneficiaries !65 and those >65. We also identified factors associated with these outcomes among Medicare beneficiaries under 65. Methods: This serial cross-sectional study used 2006e2009 Medicare Current Beneficiary Survey (MCBS) data linked with Medicare claims. Psychotropic prescription and psychiatric hospitalization were measured using claims data. Total annual Medicare spending included reimbursements from Medicare Parts A, B, and D. Repeated person-year data were analyzed using generalized estimating equation (GEE) models to examine associations between factors and outcomes among beneficiaries !65, controlling for covariates. Results: Over one-third of beneficiaries !65 used at least one psychotropic prescription annually. Annual prevalence of psychotropic prescription and psychiatric hospitalization was higher among beneficiaries !65 than those >65 (threefold and ten-fold, respectively), as well as Medicare spending. The annual prevalence of psychiatric hospitalization decreased over time among beneficiaries !65. Antidepressants were the most prevalently prescribed psychotropic drug class among beneficiaries !65. Factors associated with psychiatric services utilization and spending among beneficiaries !65 included demographics and health insurance access, self-reported health, smoking status, and comorbidities (all P ! 0.05). Conclusions: Our findings highlight the special psychiatric health care needs of Medicare beneficiaries under 65 and call for the attention of policy makers and clinicians to this understudied population. Ó 2015 Elsevier Inc. All rights reserved. Keywords: Psychotropic prescription; Psychiatric hospitalization; Medicare; Spending; Disability
Individuals under age 65 become eligible for Medicare due to their permanent disabilities, including end-stage renal disease (ESRD). This group represented 17% of the Medicare population in 2012.1 Medicare beneficiaries under 65 are a medically heterogenous population and about one-third of them are disabled as a result of a mental disorder.2,3 Compared to beneficiaries aged 65 and older, beneficiaries under 65 have lower income and poorer access to affordable supplemental insurance coverage.3,4 A Funding/support: This work was supported by the American Association of Colleges of Pharmacy (AACP) New Investigator Award. The funding source had no role in the design and conduct of the study. Conflicts of interest: All authors have no conflict of interest to disclose. * Corresponding author. Department of Health Outcomes Research and Policy, Auburn University, Harrison School of Pharmacy, 038 James E. Foy Hall, Auburn, AL 36849-5506, USA. Tel.: þ1 334 844 5818; fax: þ1 334 844 8307. E-mail address: [email protected] (J. Qian). 1936-6574/$ - see front matter Ó 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.dhjo.2015.03.005
national Medicare beneficiary survey found the rates of failure to fill one or more prescriptions in 2004 were significantly higher among beneficiaries aged 18e64 years than those aged 65 and older, and higher among beneficiaries with psychiatric conditions than those without these conditions.5 Medicare beneficiaries under 65 are a special population that deserves policy consideration to ensure adequate and affordable health insurance coverage as well as quality health care, especially for psychiatric health services. Medicare beneficiaries under 65 have received little research attention compared to senior beneficiaries.3 Previous studies have shown that the presence of mental illness with or without other comorbid conditions increases health services utilization and spending of Medicare beneficiaries.6e8 But a majority of health services research related to chronic and psychiatric conditions among the Medicare population has been focusing on beneficiaries aged 65 and older.8e10 To our knowledge, no study has examined
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factors associated with psychiatric health services utilization and spending targeting beneficiaries under 65, the subgroup of Medicare beneficiaries with significantly higher cognate and behavioral disorders. Further, policy changes over the past decade may be important and have a unique impact on the Medicare population. In 2006, Medicare Part D was implemented to subsidize the cost of prescription drugs for all Medicare beneficiaries. Evidence has shown that the implementation of Medicare Part D is associated with improvements in antidepressant use and adherence in depressed beneficiaries who were aged 65 and older and previously lacked drug coverage.11 Yet, little is known about the trends in psychiatric services utilization and spending after the implementation of Medicare Part D, especially among beneficiaries under 65. Up-to-date national estimates of and trends in psychiatric services utilization and spending after Medicare Part D could guide and promote improvement in access strategies and payment policies for this population. In addition, understanding factors impacting service utilization and spending among Medicare beneficiaries under 65 is important for policy makers and practitioners to identify young and disabled beneficiaries with high-risk and highspending so that early interventions and innovative payment and service delivery models could be tailored for this vulnerable population. In order to fill this important knowledge gap regarding trends in psychiatric services utilization and psychotropic medication use among Medicare population under 65, this study estimated and compare annual trends in any psychotropic prescription utilization, psychiatric hospitalization, and total annual Medicare spending between Medicare beneficiaries under 65 and those 65 years and older. We also identified factors associated with any psychotropic prescription utilization, psychiatric hospitalization, and spending among Medicare beneficiaries under 65.
Methods Study population and sample This serial cross-sectional study used 2006e2009 Medicare Current Beneficiary Survey (MCBS) Cost and Use data files. The MCBS is a continuous, multipurpose survey of a nationally representative sample of about 12,000 Medicare beneficiaries of all ages annually. The MCBS Cost and Use files link self-reported survey with Medicare claims to provide complete expenditure data on all received health care services. Thus, the files can support a broader range of research and policy analyses on the Medicare population than using either survey data or administrative claims data alone.12 Survey-reported data include information on the use and cost of all types of medical services, health insurance, education, income, health status, and physical functioning. Medicare claims data includes health services
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utilization and cost information on inpatient, outpatient services, and prescription drugs.12 We included nationally representative Medicare community-dwelling beneficiaries who completed the survey in 2006e2009. Beneficiaries enrolled in Medicare health maintenance organizations (HMOs) in any given year were excluded (about 22%e38% of sample, depending on year) due to their lack of complete Medicare Parts A and B claims data. The final study sample included a total of 13,971 individual beneficiaries of all ages in the 4-year study period. We included beneficiaries >65 for the purpose of comparing annual trends of psychiatric services utilization and spending with younger beneficiaries. The annual sample varied between 1048 (2009, weighted n 5 3.7 million) and 1341 (2006, weighted n 5 3.9 million) individuals for beneficiaries under 65 and between 4459 (2009, weighted n 5 18.6 million) and 5886 (2006, weighted n 5 21.1 million) individuals for beneficiaries >65. This study was determined to be exempt human subjects research by the Auburn University institutional review board (IRB). Outcomes measurements Outcome measures included any psychotropic prescription utilization (overall and by drug class), any psychiatric hospitalization, and annual total Medicare spending in 2006e2009. Any psychotropic prescription utilization was defined as having one or more antidepressants (e.g., selective serotonin reuptake inhibitors and serotoninnorepinephrine reuptake inhibitors), antipsychotics (e.g., typical and atypical antipsychotics), stimulants (e.g., dextroamphetamine and methylphenidate), mood stabilizers (e.g., lamotrigine and carbamazepine), anxiolytics (e.g., benzodiazepines), hypnotics (e.g., temazepam and phenobarbital), or antimanic drugs (e.g., lithium) captured in Medicare prescription claims data. Any psychiatric hospitalization included any inpatient hospital stay with a primary admission diagnosis of depression, anxiety, bipolar disorder, alcohol or drug abuse, schizophrenia and other psychotic disorders in Medicare inpatient hospital claims data. These psychiatric disorders were defined using the algorithms and International Classification of Diseases, ninth revision (ICD-9-CM) diagnosis codes developed by the Centers for Medicare & Medicaid Services (CMS) Chronic Condition Warehouse.13 Annual total Medicare spending included all beneficiary-level expenditures reimbursed through Medicare Parts A, B, and D during each calendar year. Part A reimbursements included Medicare payment for hospital care, skilled nursing facility care, hospice, and home health services. Part B reimbursements included Medicare payment for outpatient care, physician office visits, and durable medical equipment. Part D reimbursements included amount paid by Medicare for any prescription claims. To ensure comparability of Medicare spending results over
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the 4-year study period, all spending amounts were inflated to constant 2009 US dollars using the urban Medical Component of the Consumer Price Index.14 Factors associated with outcomes In order to identify factors associated with any psychotropic prescription utilization, any psychiatric hospitalization, and total annual Medicare spending among beneficiaries under 65, the following factors were assessed: demographic characteristics, socioeconomic factors, health insurance benefit variables, self-reported health and smoking status, and comorbidity. Demographic characteristics included age (0e44 and 45e64), gender (male and female), race/ethnicity (white, black, Hispanic, and other), and region (Northeast, Midwest, South, and West). Socioeconomic factors included marital status (married, widowed, divorced, and other) and self-reported education (no or some high school, high school graduate, and some college or more). Additionally, two binary health insurance benefit variables (low-income subsidy and Medicare-Medicaid dual eligibility) were also identified. Since Medicare provides premium subsidies for low-income beneficiaries who enrolled in Medicare Part D prescription plans (PDP), we defined a beneficiary’s low-income subsidy status as ‘‘yes’’ if he/she received any premium subsidies in any month of a year. Medicare-Medicaid dual eligibility was defined as ‘‘yes’’ if a beneficiary was enrolled in Medicaid at least one month of a year. Further, self-reported health status (excellent or good, fair, and poor), self-reported current smoking status (yes and no), and count of chronic comorbidities were also assessed. In the MCBS Cost and Use Health Status & Functioning (community) survey, beneficiaries were asked about their ‘‘general health compared to others at the same age’’ and if they ‘‘smoke now.’’ We used these two questions to define beneficiary’s self-reported health status and current smoking status. We also identified a total of 11 prevalent chronic comorbidities in the Medicare population using the algorithms and ICD-9-CM diagnosis codes developed by the CMS Chronic Condition Warehouse in the linked Medicare claims data.13 These comorbidities included acute myocardial infarction, asthma, chronic obstructive pulmonary disease, chronic kidney disease, diabetes, heart failure, hyperlipidemia, hypertension, ischemic heart disease, stroke, and osteoporosis. We then counted the comorbidities they had in any given year and further categorized as 0, 1, 2, and 3 or more chronic comorbidities. Statistical analysis Annual prevalence and mean trends of any psychotropic prescription utilization and psychiatric hospitalization, as well as trends of annual mean total Medicare spending per beneficiary were estimated for each calendar year for
beneficiaries !65 and those >65. Trends of annual mean total Medicare spending, and by subcategory (i.e., Medicare Parts A, B, and D) per beneficiary were estimated across years. Linear regression models were used to test for trends in the annual prevalence, means, and spending over time for both age groups. In addition, we combined beneficiaries !65 and those >65 in linear regression models and compared their outcome estimates by testing the dummy variable of age group. We also pulled all psychotropic prescription utilization by therapeutic class over the 4 years and estimated proportion of individual therapeutic classes for beneficiaries !65 and those >65. To identify factors associated with having any psychotropic prescription utilization (overall and by drug class), psychiatric hospitalization, and annual total Medicare spending among beneficiaries under 65, a total of 4864 person-years were derived from the 4-year data for bivariable and multivariable analyses. The bivariable analyses (Chisquare) compared factors between beneficiaries with and without any psychotropic prescription utilization and psychiatric hospitalization. Since an individual beneficiary could contribute up to three person-years of observations in the MCBS data, seven multivariable models with generalized estimating equations (GEE) were used to examine the conditional effects of factors on outcomes. GEE models are particularly useful for modeling clustered/correlated data (e.g., repeated observations among subjects) to achieve efficient parameter estimations and accurate standard errors (SEs).15 The first GEE model (Model 1) examined the associations between factors and any use of psychotropic prescription. GEE models 2e5 examined the associations between factors and any use of antidepressants, antipsychotics, mood stabilizers, and other psychotropic prescription (defined as combined use of hypnotics, antimanics, anxiolytics, and stimulants due to small proportions), respectively. Further, another GEE model (Model 6) was used to identify factors associated with any psychiatric hospitalization. In this model, two factors were re-categorized (i.e., race/ethnicity and marital status) due to small cell sizes (unweighted n ! 20) to maintain the stability of multivariable models.16 Models 1e6 used modified Poisson regression and a log link function to estimate prevalence ratios (PRs) with associated 95% confidence intervals (CIs). The last GEE model (Model 7) included two additional binary independent variables (any use of psychotropic prescription and psychiatric hospitalization) to predict annual total Medicare spending among those beneficiaries under 65 with any positive Medicare spending in 2006e2009 (n 5 4189 person years). In this modified generalized linear model (GLM) with GEE approach, a gamma distribution and log link function were used to handle the highly right-skewed health care spending data.17 To facilitate interpretation, the coefficients from Model 7 examining factors associated with higher annual total Medicare spending were converted to a marginal mean difference (MDD) with 95% CIs to show the magnitude of spending
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associated with specific factors after controlling for all other factors. In all multivariable models, the factor ‘‘low-income subsidy’’ was removed to avoid multicollinearity due to the substantial overlap with MedicareMedicaid dual eligibility. Results from all trend analyses, bivariable analyses, and multivariable models were weighted using the cross-sectional sampling weights provided in the MCBS data files to generate nationally representative estimates. All analyses were performed using SAS 9.2 (SAS Institute, Inc., Cary, NC). Statistical significance was set at P ! 0.05.
Results Results from trend analyses Over one-third (38.4%) of Medicare beneficiaries under 65 filled at least one psychotropic prescription annually. The annual prevalence of any psychotropic prescription utilization among beneficiaries under 65 increased from 34.8% in 2006 to 40.1% in 2009, compared with 12.4% e14.0% for those 65 years and older (Fig. 1, Panel a). The prevalence of psychotropic prescription was significantly higher in beneficiaries under 65 than those 65 and older (P ! 0.0001). But neither trend in prevalence of psychotropic prescription exhibited statistical significance over time in younger or aged beneficiaries (P 5 0.13 and P 5 0.20, respectively). The annual means of any psychotropic prescription utilization per beneficiary for beneficiaries under 65 was 9.9 (standard error (SE) 5 0.92) in 2006 and 9.4 (SE 5 0.30) in 2009 compared to 5.4 (SE 5 0.37) in 2006 and 6.1 (SE 5 0.17) in 2009 for older beneficiaries (Fig. 1, Panel b). Similarly, the mean number of psychotropic prescriptions was significantly higher in beneficiaries under 65 than those 65 and older (P ! 0.001). But neither trend in means of psychotropic prescription showed statistical significance over time in younger or aged beneficiaries (P 5 0.43 and P 5 0.20, respectively).
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The annual prevalence of any psychiatric hospitalization among beneficiaries under 65 was ten-fold higher than those 65 years and older. The prevalence decreased from 2.6% in 2006 to 1.9% in 2009 for beneficiaries under 65, compared with 0.2% in 2006 to 0.3% in 2009 for those >65 (Fig. 1, Panel a). The comparison in prevalence estimates of psychiatric hospitalization showed that beneficiaries under 65 had a higher prevalence than those 65 and older (P ! 0.0001). Trend analysis also confirmed the decreased trend in psychiatric hospitalization among beneficiaries under 65 (borderline P 5 0.05) and increased trend in psychiatric hospitalization among older beneficiaries (P 5 0.02). The annual means of any psychiatric hospitalization per beneficiary were similar and remained stable across year for both groups, accounting for approximately one hospitalization per beneficiary per year (Fig. 1, Panel b). For beneficiaries under 65, the most commonly prescribed psychotropic drug classes were antidepressants (28.7%), antipsychotics (14.1%), and mood stabilizers (9.6%), followed by hypnotics (8.8%) and anxiolytics (5.2%). Stimulants and antimanics were the least prescribed psychotropic drug classes among beneficiaries under 65, with annual prevalence around 1% (Fig. 2). For beneficiaries >65, the most prevalently prescribed psychotropic drug classes were antidepressants (9.8%), hypnotics (3.4%), antipsychotics (1.9%), and anxiolytics (1.8%). Mood stabilizers, stimulants, and antimanics were the least prescribed psychotropic drug classes among beneficiaries >65 with annual prevalence less than 1%. The annual total Medicare spending per beneficiary increased across years for both groups e from $9695 (SE 5 $727) in 2006 to $11,391 (SE 5 $729) in 2009 for beneficiaries under 65, compared with $8820 (SE 5 $207) to $9357 (SE 5 $318) for beneficiaries >65. Beneficiaries under 65 had lower annual Part A spending (P 5 0.04), similar annual Part B spending (P 5 0.24), and much higher annual total and Part D spending compared with those 65 years and older (both P ! 0.01) (Fig. 3). Although trend analysis in annual total
Fig. 1. Trends in prevalence and means of psychotropic prescription and psychiatric hospitalization among Medicare beneficiaries in 2006e2009 (weighted).
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Fig. 2. Weighted total proportions of psychotropic prescription utilization by therapeutic class among Medicare beneficiaries in 2006e2009.
or Part A Medicare spending per beneficiary did not exhibit statistical significance over time in either age group, aged beneficiaries had increased annual Part B and Part D over time (P 5 0.01 and P 5 0.03, respectively). Beneficiaries under 65 also had increased annual Part B spending over time (P 5 0.04), but the trend in Part D spending did not show statistical significance (P 5 0.33). Results from bivariable and multivariable analyses Among all beneficiaries under 65, bivariable analyses found that age, sex, marital status, education, health insurance benefits, self-reported health and current smoking statuses, counts of chronic comorbidities, and time (in year) were statistically different between psychotropic prescription users and non-users (all P ! 0.05). Age, health insurance benefits, and self-reported current smoking status were statistically different between those with and without any psychiatric hospitalization (all P ! 0.05, Table 1). After controlling for all other factors, multivariable results found that the prevalence of any psychotropic prescription utilization was higher in beneficiaries under 65 with younger age (0e44), female sex, white race (vs. black), being divorced, with no or some high school education (vs. those with some college or more), being MedicareMedicaid dual eligible, with poorer health status and currently smoking, and having 1 or more chronic comorbidities (all P ! 0.05, Table 2). In models examining factors associated with different psychotropic drug classes, younger age, certain marital status, and being MedicareMedicaid dual eligible were associated with higher likelihood of use of any antidepressants, antipsychotics, mood stabilizers, and other psychotropic drug classes. Female sex also was associated with higher use of different
psychotropic drug classes except for antipsychotics. White race/ethnicity was associated with higher use of antidepressants and mood stabilizers compared with blacks. Poorer health status was associated with higher use of antidepressants and other psychotropic drug classes except for antipsychotics and mood stabilizers. Concurrent smoking was associated with higher use of antidepressants and antipsychotics. Having more comorbidities was associated with different psychotropic drug classes except for mood stabilizers (all P ! 0.05, data not shown). Multivariable results found that the prevalence of any psychiatric hospitalization was higher in beneficiaries under 65 with younger age (0e44), being MedicareMedicaid dual eligible, currently smoking, and having 2 (compared to zero) chronic comorbidities (all P ! 0.05, Table 2). We also found that beneficiaries under 65 with any use of psychotropic prescriptions had an average of $5620 (95% CI 5 $3,825, $7700) more annual Medicare spending compared to those without. Those with any psychiatric hospitalization had an average of $12,531 (95% CI 5 $7,865, $18,466) more annual Medicare spending compared to those without. In addition, for beneficiaries under 65 who were younger in age, African American (vs. white), with higher education, Medicare-Medicaid dual eligible, with poorer health status and more chronic comorbidities also had higher annual total Medicare spending (all P ! 0.05, Table 2).
Discussion This study fills an important knowledge gap in psychiatric health services utilization and spending among Medicare beneficiaries under 65 e those with physical or
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Fig. 3. Trends in annual mean Medicare spending (total and by category) among Medicare beneficiaries in 2006e2009 (weighted).
mental disabilities. Our findings not only highlight the special health care needs of Medicare beneficiaries under 65, but also draw policy and practice attention to ensuring adequate and affordable health insurance coverage as well as high quality psychiatric health services for this vulnerable population. We found that the annual prevalence of any psychotropic prescription or psychiatric hospitalization was much higher among disabled beneficiaries under 65 compared to older beneficiaries, with a threefold higher prevalence of any psychotropic prescription and a ten-fold higher prevalence of psychiatric hospitalization, respectively. Although our trend analyses did not show the increased trends in annual prevalence of psychotropic prescription over time for either age group after the implementation of Medicare Part D, we found an increased trend in the prevalence of psychiatric hospitalization among older beneficiaries but a decreased trend in the prevalence of psychiatric hospitalization among beneficiaries under 65 during the same time period. We also found that total annual Medicare costs were approximately $2000 more for a beneficiary under 65 compared to a beneficiary >65. Our results demonstrated that aged beneficiaries had increased trend in annual Part B and Part D spending in 2006e2009. Beneficiaries under 65 also had an increased trend in annual Part B spending over time but not in Part D spending. Independent of demographic and socioeconomic factors, health status, and comorbidities, we found that being dually eligible for Medicare and Medicaid was associated with
higher likelihood of any psychotropic prescription utilization, overall and by drug class, among Medicare beneficiaries under 65. Beneficiaries who were MedicareMedicaid eligible had more than a twofold higher likelihood of any psychotropic prescription compared to those who were not eligible. Our results are consistent with Stuart et al18 and suggest that the Medicare low-income subsidy (99.8% of beneficiaries under 65 also received lowincome subsidy in this sample, which was weighted for 59.1% of beneficiaries under 65 nationwide) and Part D might provide meaningful assistance in removing costrelated barriers to medication use and increase access to medications for qualified beneficiaries. Our model also identified factors associated with psychiatric hospitalization among beneficiaries under 65. We found that younger age, being dual eligible for Medicare and Medicaid, currently smoking, and having 2 chronic comorbidities were associated with higher likelihood of psychiatric hospitalization. Specifically, younger (age 0e44) beneficiaries and those eligible for both Medicare and Medicaid had more than a twofold higher likelihood of psychiatric hospitalization than older (age 45e64) beneficiaries and those not dual eligible. Future research is needed to confirm these findings so that practitioners and policy makers might consider these patient subgroups as high priority for outpatient case management in an effort to minimize hospitalization risk and improve clinical outcomes for these patients.
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Table 1 Characteristics of the sample of Medicare beneficiaries under 65 (weighted n 5 15,145,931 person-years) Any use of psychotropic prescription Any use of psychiatric hospitalization Users
Nonusers
Users Pa
Characteristics
Weighted %
Person-years Demographics Age (year) 0e44 45e64 Sex Female Male Race/ethnicityb White Black Hispanic Other Region Northeast Midwest South West Socioeconomic factors Marital status Married Widowed Divorced Otherc Education No or some high school High school graduate Some college or more Health insurance benefit Low-income subsidy Medicare-Medicaid dual eligibility Self-report health status Excellent or good Fair Poor Self-report current smoking status Smoking now Count of chronic comorbidities 0 1 2 3 and more Year 2006 2007 2008 2009
38.4
61.6
31.2 68.8
21.6 78.4
57.5 42.5
39.3 60.7
75.3 17.1 3.2 4.4
71.2 21.4 3.2 4.2
20.5 21.6 44.1 13.8
18.0 22.1 45.0 14.9
20.8 7.5 29.9 41.8
40.9 6.6 22.5 30.0
35.8 35.1 29.2
30.3 31.5 38.2
86.3 70.6
42.1 32.6
40.0 33.4 26.5
46.4 34.4 19.2
44.9
32.6
33.6 25.1 16.6 24.7
50.0 16.9 13.9 19.2
22.7 25.3 26.7 25.3
26.7 25.7 23.8 23.7
Nonusers Pa
Weighted % 2.3
97.7
48.1 51.9
24.8 75.2
46.0 54.0
46.3 53.7
74.2 19.6 4.8 1.4
72.7 19.8 3.1 4.4
23.0 25.9 38.1 13.0
18.9 21.8 44.8 14.5
15.4 0 26.1 58.5
33.6 7.1 25.3 34.0
34.3 31.8 33.9
32.4 32.9 34.8
84.7 74.3
58.5 46.6
44.8 34.9 20.2
43.9 34.0 22.1
63.3
36.7
39.7 19.3 20.8 20.3
43.8 20.1 14.8 21.3
27.7 29.2 23.2 19.9
25.1 25.5 25.0 24.4
!0.01
!0.01
!0.01
0.95
0.20
0.06
0.66
0.62
!0.01
N/A
!0.01
!0.01 !0.01 !0.01
!0.01 !0.01
0.95
0.02
!0.01 !0.01 0.89
!0.01 0.51
0.64
N/A: not applicable. a Chi-square tests. b We used the race code in the MCBS Cost and Use Administrative Identification file to determine race/ethnicity category. The original race code includes white, black, Hispanic, Asian, North American Native, other, and unknown. We merged Asian, North American Native, other, and unknown into a new ‘‘Other’’ category in this study. c Including separated, never married, refused, and don’t know.
We found that Medicare spent much more for beneficiaries under 65 with psychiatric-related health care services than those without such services. For example, our results indicate that having any psychotropic prescription
and psychiatric hospitalization was associated with a $5620 and $12,531 higher annual Medicare spending per beneficiary under 65, respectively, after controlling for all other factors. According to a 2004 Agency for Healthcare
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Table 2 Associations between factors with use of psychotropic prescription, psychiatric hospitalization, and annual total Medicare spending among Medicare beneficiaries under 65 Any psychotropic prescriptiona Any psychiatric hospitalizationa Annual mean total Medicare spendingb Factors
PR
95% CI
PR
95% CI
MMD
95% CI
Any use of psychotropic prescription Any psychiatric hospitalization Demographics Age (year) 0e44 45e64 Sex Female Male Race/ethnicityc White Black Hispanic Other Non-whited Region Northeast Midwest South West Socioeconomic factors Marital status Married Widowed Divorced Otherf Widowed or divorcedg Education No or some high school High school Some college or more Medicare-Medicaid dual eligibility Self-report health status Excellent or good Fair Poor Self-report current smoking status Smoking now (vs. Never smoke/ previous smoke) Count of chronic comorbidities 0 1 2 3 and more
N/A N/A
N/A N/A
N/A N/A
N/A N/A
$5620e $12,531e
$3825, $7700e $7865, $18,466e
Reference 0.87e 0.80e0.95e
Reference 0.45e
0.27e0.75e
Reference $1512e
$2794, $23e
Reference 0.69e 0.61e0.77e
Reference 0.96
0.58e1.59
Reference $549
$742, $2036
Reference 0.67e0.91e 0.78e 0.93 0.67e1.28 0.99 0.76e1.29 N/A N/A
Reference N/A N/A N/A 0.81
N/A N/A N/A 0.48e1.37
Reference $2409e $1794 $1177 N/A
$342, $4927e $1003, $5553 $3137, $1424 N/A
Reference 0.91 0.78e1.08 0.92 0.79e1.07 0.89 0.74e1.08
Reference 0.86 0.77 0.68
0.45e1.63 0.42e1.42 0.31e1.51
Reference $176 $980 $79
$1946, $2858 $2722, $1180 $2070, $2814
Reference 1.20 0.99e1.46 1.31e 1.13e1.52e e 1.30 1.13e1.50e N/A N/A
Reference N/A N/A 2.07e 1.25
N/A N/A 1.07e4.02e 0.63e2.50
Reference $1437 $1796 $2002 N/A
$696, $4167 $11, $3994 $88, $4585 N/A
Reference 1.01 0.89e1.14 0.87e 0.75e1.00e e 2.04 1.77e2.36e
Reference 1.08 1.29 2.21e
0.61e1.90 0.77e2.19 1.26e3.88e
Reference $2215e $2022e $1837e
$416, $4390e $297, $4096e $45, $4000e
Reference 1.06e 1.00e1.13e e 1.12 1.04e1.21e
Reference 1.08 0.93
0.69e1.70 0.58e1.50
Reference $1511e $4350e
$308, $2884e $2627, $6348e
1.16e
2.57e
1.71e3.84e
$1042
$2349, $487
Reference 1.26 1.80e 1.59
0.82e1.96 1.14e2.87e 0.90e2.79
Reference $2695e $6096e $18,036e
1.07e1.27e
Reference 1.10e 1.02e1.20e 1.15e 1.05e1.26e e 1.20 1.10e1.31e
$1537, $4053e $3899, $8823e $14,050, $22,846e
PR: prevalence ratio; CL: confidence interval; MMD: marginal mean difference; N/A: not applicable. a Generalized estimating equations (GEE) multivariable models were performed to examine the conditional effects of identified factors on psychotropic prescription use and any psychiatric hospitalization. Results were weighted using MCBS averaged weights. Weighted n 5 15,145,931 person-years. b GEE multivariable model was performed to examine the marginal effects of identified factors on annual Medicare spending among those who had any Medicare spending during each year. Results were weighted using MCBS averaged weights. All spending were converted to 2009 US dollars. Weighted n 5 12,858,122 person-years. c We used the race code in the MCBS Cost and Use Administrative Identification file to determine race/ethnicity category. The original race code includes white, black, Hispanic, Asian, North American Native, other, and unknown. We merged Asian, North American Native, other, and unknown into a new ‘‘Other’’ category in this study. d Including African American, Hispanic, and other. This racial category was only appeared in the GEE model examining factors associated with any psychiatric hospitalization. e Statistically significant at P ! 0.05. f Including separated, never married, refused, and don’t know. g Including those who were either widowed or divorced. This marital status category was only appeared in the GEE model examining factors associated with any psychiatric hospitalization.
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Research and Quality (AHRQ) analysis, 22% of total hospital costs were attributable to adults with mental or substance use disorder and hospital stays involving these disorders were 29% longer than stays for other conditions.19 Our results may help policy makers identify potential disparities in Medicare spending: the substantial Medicare spending associated with factors such as race/ ethnicity, education, Medicare-Medicaid dual eligibility, health status, and count of chronic comorbidities may help policy makers shape quality improvement and cost containment efforts around these areas. Our findings highlight the need for providing adequate and affordable health insurance coverage of psychiatric health services for beneficiaries under 65. Indeed, over one-third of these young and disabled beneficiaries filled at least one psychotropic prescription annually, which makes them more sensitive to prescription formulary changes related to psychiatric drugs under Medicare Part D. In January 2014, CMS proposed to revise prior policy that required Part D plans to include on their formularies ‘‘all or substantially all’’ drugs including antidepressants and antipsychotics. The agency planned to exclude antidepressants, and potentially antipsychotics, from this ‘‘six protected classes’’ policy. This and similar proposals, if approved, will lead to a reduction in the numbers of medications available on Part D plan formularies for all Medicare beneficiaries. This has a possibility for unintended consequences. For example, the Oregon state Medicaid cutbacks on individuals with schizophrenia in 2003 were associated with increased state psychiatric hospitalization utilization among those who lost Medicaid coverage.20 Providing the needed psychiatric services would generate cost savings if patients adhere to treatment, avoid hospitalization, and have less use of costly services. Thus, policy makers should pay attention to health policy changes related to psychiatric services that could impact Medicare beneficiaries under 65 and ensure adequate prescription coverage for this vulnerable population. More work is needed to assess these implications at the drug level or among more narrowly defined subgroups. This study has several limitations. The cross-sectional study design only examined association instead of causality. Using diagnosis codes to ascertain psychiatric hospitalization and comorbidities could lead to disease misclassification. Further, our estimate of health services utilization and spending could only capture services paid by Medicare and missed those financed through other sources such as Medicaid or private insurance. The comparison between young and older Medicare beneficiaries could be influenced by differential survivorship, which might lead to underestimation of psychiatric service utilization and spending among beneficiaries 65 years and older. In addition, the self-reported variables identified from the MCBS data might introduce self-report bias. Beneficiaries enrolled in Medicare due to ESRD might present different health care utilization and spending from other beneficiaries under
65. Our data had limited statistical power to estimate such potential differences because of the low representative sample of ESRD enrollees (!2.0%) among beneficiaries under 65. Finally, results from this study may not be generalizable to Medicare beneficiaries enrolled in HMOs.
Conclusions In conclusion, this study fills important knowledge gaps of psychiatric health services utilization and spending among Medicare beneficiaries under 65. Findings highlight the special health care needs of young and disabled Medicare beneficiaries and identify certain factors impacting their likelihood of psychiatric services utilization and spending. Future research should dig deeper into understanding access to and quality of psychiatric services and utilization for this understudied population. References 1. Merrick EL, Perloff J, Tompkins CP. Emergency department utilization patterns for Medicare beneficiaries with serious mental disorders. Psychiatr Serv. Jun 2010;61(6):628e631. 2. Social Security Administration. Annual Statistical Report on the Social Security Disability Insurance Program, 2007. SSA Publication No.13e11826. Released August 2008. Available at: http://www.ssa.gov/ policy/docs/statcomps/di_asr/2007/di_asr07.pdf; Accessed 08.08.12. 3. Kennedy J, Tuleu IB. Working age Medicare beneficiaries with disabilities: population characteristics and policy considerations. J Health Hum Serv Adm. Winter 2007;30(3):268e291. 4. Cubanski J, Neuman P. Medicare doesn’t work as well for younger, disabled beneficiaries as it does for older enrollees. Health Aff (Millwood). Sep 2010;29(9):1725e1733. 5. Kennedy J, Tuleu I, Mackay K. Unfilled prescriptions of Medicare beneficiaries: prevalence, reasons, and types of medicines prescribed. Journal of managed care pharmacy. JMCP. JuleAug 2008;14(6): 553e560. 6. Dobrez D, Heinemann AW, Deutsch A, Durkin EM, Almagor O. Impact of mental disorders on cost and reimbursement for patients in inpatient rehabilitation facilities. Arch Phys Med Rehabil. Feb 2010;91(2):184e188. 7. Unutzer J, Schoenbaum M, Katon WJ, et al. Healthcare costs associated with depression in medically ill fee-for-service medicare participants. J Am Geriatr Soc. Mar 2009;57(3):506e510. 8. Himelhoch S, Weller WE, Wu AW, Anderson GF, Cooper LA. Chronic medical illness, depression, and use of acute medical services among Medicare beneficiaries. Med Care. Jun 2004;42(6):512e521. 9. Prince JD, Akincigil A, Kalay E, et al. Psychiatric rehospitalization among elderly persons in the United States. Psychiatr Serv. Sep 2008;59(9):1038e1045. 10. Huang H, Chan YF, Bauer AM, et al. Specialty behavioral health service use among chronically ill Medicare advantage patients with substance use problems. Psychosomatics. NoveDec 2013;54(6): 546e551. 11. Donohue JM, Zhang Y, Aiju M, et al. Impact of Medicare Part D on antidepressant treatment, medication choice, and adherence among older adults with depression. Am J Geriatr Psychiatry. Dec 2011;19(12):989e997. 12. Centers for Medicare & Medicaid Services: Medicare Current Beneficiary Survey (MCBS). Available at: https://www.cms.gov/ResearchStatistics-Data-and-Systems/Research/MCBS/index.html?redirect5/M CBS/; Accessed 03.04.13.
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17. Barber J, Thompson S. Multiple regression of cost data: use of generalised linear models. J Health Serv Res Policy. Oct 2004;9(4): 197e204. 18. Stuart B, Yin X, Davidoff A, et al. Impact of Part D low-income subsidies on medication patterns for Medicare beneficiaries with diabetes. Med Care. Nov 2012;50(11):913e919. 19. Owens P, Myers M, Elixhauser A, Brach C. Care of Adults With Mental Health and Substance Abuse Disorders in US Community Hospitals, 2004eHCUP Fact Book No. 10. Rockville, MD: Agency for Healthcare Research and Quality; 2004. 20. McFarland BH, Collins JC. Medicaid cutbacks and state psychiatric hospitalization of patients with schizophrenia. Psychiatr Serv. Aug 2011;62(8):871e877.
