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ScienceDirect Comprehensive Psychiatry 55 (2014) 1855 – 1861 www.elsevier.com/locate/comppsych
Correlates of psychiatric hospitalization in a clinical sample of Canadian adolescents with bipolar disorder Joshua Shapiro a, b , Vanessa Timmins a , Brenda Swampillai a , Antonette Scavone a , Katelyn Collinger a , Carolyn Boulos a , Jessica Hatch a , Benjamin I. Goldstein a,⁎ a
Department of Psychiatry, Sunnybrook Health Sciences Centre, Toronto, ON, Canada b Wilfrid Laurier University, Waterloo, ON, Canada
Abstract Objective: To identify factors associated with psychiatric hospitalization among adolescents with bipolar disorder (BD). Methods: Participants were 100 adolescents, ages 13–19, who fulfilled DSM-IV criteria for bipolar I disorder [(BD-I), n = 26], bipolar II disorder [(BD-II), n = 40], or operationalized criteria for BD not otherwise specified [(BD-NOS), n = 34], via the Schedule for Affective Disorders and Schizophrenia, Present and Lifetime version (KSADS-PL). Demographic, clinical, and family history variables were measured via clinical interview with the participant and a parent or guardian. Results: The lifetime prevalence of psychiatric hospitalization was 50%. Significant predictors of psychiatric hospitalization in univariate analyses included older age, BD-I, history of suicide attempt, psychosis, lifetime use of second generation antipsychotics (SGAs), lithium, SSRI antidepressants and any medication. BD-II was negatively associated with psychiatric hospitalization. In multivariable analyses, older age, history of suicide attempt, psychosis and use of SGAs were positively associated with hospitalization, whereas BD-II was negatively associated with hospitalization. Conclusions: Psychiatric hospitalization in adolescents with BD is highly prevalent and associated with older age and proxies for greater illness severity. Further studies are needed to identify strategies for reducing the need for psychiatric hospitalizations among adolescents with BD. © 2014 Elsevier Inc. All rights reserved.
1. Introduction Bipolar disorder (BD) is a recurrent and impairing illness that is associated with substantial burden of mood symptoms and comorbidity among adults and youth [1–3]. BD often requires high treatment usage [4], and more than 75% of adults with BD report one or more lifetime psychiatric hospitalizations [5]. With widespread decreases in the number of psychiatric beds, psychiatric hospitalization in recent years is often precipitated by acute crises that necessitate hospitalization for the purpose of risk containment. As such, psychiatric hospitalization is often a decision driven by immediate need rather than individual preferences among patients, families,
⁎ Corresponding author at: Centre for Youth Bipolar Disorder, Sunnybrook Health Sciences Centre; 2075 Bayview Ave., Room FG-53. Tel.: +1 416 480 5328. E-mail address: [email protected] (B.I. Goldstein). http://dx.doi.org/10.1016/j.comppsych.2014.08.048 0010-440X/© 2014 Elsevier Inc. All rights reserved.
and/or practitioners. Concerns about hospitalization relate to the disruptive and distressing experience psychiatric hospitalization can be for patients with BD and their families, and the substantial costs incurred [6,7]. The overall treatment costs of patients with BD have been found to exceed those for other behavioral and mood disorders [8–10], a disparity that is attributable in large part to hospitalizations which account for 20% of these costs [11]. Investigation of clinical characteristics associated with hospitalization can potentially help align outpatient treatment focus toward preventing these outcomes and identify patients at risk for hospitalization. Hospitalizations among adults with BD have been associated with substance use disorders (SUD) [12–15], rapid cycling [16,17], psychosis [18], previous hospitalization [19,20], BD-I subtype [21], female gender [22,23], various medications [11,16–18,24–28], minority status [18], polypharmacy [27], and marital separation [13]. While there is a larger literature on this topic among adults with BD, there is a growing body of literature regarding the rates and correlates of psychiatric hospitalization among
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adolescents with BD. Hospitalization rates for psychiatric disorders in youth, especially BD, have increased markedly in the past 20 years [29–33]. The annual rate of hospitalization among adolescents with BD in the US was found to be 39.6% in 2003 [8]. Annual rates in children and adolescents increased 434% between 1997 and 2010 [29], which coincided with a large increase in number of BD diagnoses for this age group [30,31]. Adolescents with BD are hospitalized more often than those with most other psychiatric and behavioral disorders [34–37], and rates of inpatient service use now exceed even those of adults with BD in some reports [22]. Female gender [38,39], comorbid health conditions [39] and having a parent with SUD [38] have all been shown to be directly associated with hospitalization in adolescents with BD, while suicidal or self-injurious behavior [35], comorbid physical conditions in general [39] and rapid cycling [38] are associated with use of highly restrictive treatment settings. The purpose of this report is to expand the literature on mental health service use among adolescents with BD by investigating characteristics associated with psychiatric hospitalization in a treatment-seeking sample from a subspecialty clinic at a tertiary academic health sciences center in Canada. Most previous studies on the topic of psychiatric hospitalizations among youth with BD are derived from American populations, and differences in the two nations' health care systems [40,41] suggest the need to examine this topic among Canadian adolescents specifically. In particular, the absence of universal healthcare to date may render barriers that are not present in socialized healthcare [42], which may cause for differences in factors associated with psychiatric hospitalization.
2. Methods 2.1. Sample and setting The present study includes 100 participants, ages 13–19, with BD-I (n = 26), BD-II (n = 40), or BD-not otherwise specified (NOS; n = 34). Participants were seeking outpatient assessment and/or treatment at a sub-specialty clinic in a tertiary academic health sciences center. Written informed consent was provided by parent(s) and adolescent before study commencement. Research ethics board approval was obtained. At least one parent/guardian for each adolescent also participated. 2.2. Subject assessment Diagnoses (current and lifetime) were determined via the Schedule for Affective Disorders and Schizophrenia, Present and Lifetime version (KSADS-PL) [43], which incorporates information from adolescents and their parent(s). Similarly, lifetime history of psychiatric hospitalization was ascertained during the KSADS-PL interview. Primary cause of hospitalization was determined through review of available patient charts. All interviewers had a bachelor's or master's
degree in a mental health field and completed comprehensive KSADS training under the supervision of the senior author (B.G.). The KSADS Depression Rating Scale (DEP-P) [44] and KSADS Mania Rating Scale (MRS) [45] were used in place of the mood sections of the KSADS-PL. Diagnoses were determined with the consideration of all available information and clinical judgment was used when conflicting information was provided. Diagnoses were confirmed by a consensus meeting with a child psychiatrist following completion of the KSADS-PL interview (B.G.). This study employed operationalized criteria for BD-NOS as described in the Course and Outcome of Bipolar Youth (COBY) study [46]: elevated and/or irritable mood, plus (i) two DSM-IV manic symptoms (three if only irritable mood is reported), (ii) change in functioning, (iii) mood and symptom duration of at least 4 h during a 24-h period, and (iv) at least four cumulative 24-h periods of episodes over the participant's lifetime that meet the mood, symptom severity, and functional change criteria. The age of onset of an individual's BD was considered to be when the participant first met DSM-IV criteria for a manic, hypomanic, or major depressive episode, or when he/she first met study criteria for BD-NOS. A self-reported medical history questionnaire and the post-traumatic stress disorder (PTSD) screen within the KSADS-PL were used to obtain history of physical and sexual abuse. A Safety Assessment Form, an intervieweradministered questionnaire, was used to determine lifetime aggression and suicidality that may have occurred outside of the context of a depressive episode. The Conflict Behavior Questionnaire (CBQ) self-report assesses family conflict and was completed by parents regarding their adolescent [47]. Psychiatric status and history of first- and second-degree relatives was obtained through an interview with the adolescent and parent(s), using the Family History Screen [48]. Socioeconomic status was determined via the 4-factor Hollingshead Scale [49]. 2.3. Data analysis Variables were screened for their association with lifetime psychiatric hospitalization using chi-square tests for categorical variables and t-tests for continuous variables. For the purpose of this analysis, the dimensional CBQ, LPI and CALS questionnaires were dichotomized as high score versus low score on the basis of a median split. Demographic and clinical characteristics and comorbidities that were associated with psychiatric hospitalization (p b 0.1) in the univariate analyses were entered into a backward elimination Wald logistic regression model in order to examine the unique contribution to variance in psychiatrics hospitalizations associated with each predictor, controlling for the effects of other predictors. All p values are based on two-tailed tests with a significance level of α = 0.05. Statistical correction for multiple comparisons was not applied as information on the correlates of psychiatric hospitalization in this population is scarce,
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especially since youth with BD-II and BD-NOS were included. The Statistical Package for the Social Sciences Version 20 (SPSS) was used to perform statistical analyses.
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group differences in prevalence of these familial conditions were observed. 3.3. Logistic regression analysis
3. Results 3.1. Socio-demographic characteristics of adolescents with bipolar disorder who had a psychiatric hospitalization Socio-demographic characteristics of all participants are portrayed in Table 1. Of the 100 adolescents with BD, 50% had at least one lifetime psychiatric hospitalization. Participants with, versus without, a history of psychiatric hospitalization were significantly older. Gender, race, socioeconomic status and living with both natural parents were not significantly associated with psychiatric hospitalization. 3.2. Clinical and familial characteristics of adolescents with bipolar disorder who had a psychiatric hospitalization A comparison of clinical characteristics distinguishing those who have a lifetime psychiatric hospitalization to those who have not is portrayed in Table 2. BD subtype was significantly associated with psychiatric hospitalization. A post-hoc univariate analysis of the three BD subtypes revealed that patients with BD-I were significantly more likely to have a psychiatric hospitalization, while patients with BD-II were significantly less likely. Participants with, versus without, lifetime psychiatric hospitalization were significantly more likely to have lifetime psychosis, lifetime suicide attempt, and trended toward lower prevalence of comorbid attention deficit hyperactivity disorder (ADHD) (p = 0.07). Participants with lifetime psychiatric hospitalization were also significantly more likely to have lifetime use of lithium, SSRI antidepressants, second generation antipsychotics (SGAs) and any medication. First- and second- degree family history of mania or hypomania, major depressive episode, ADHD, conduct disorder, anxiety and substance dependence is displayed in Table 3. No significant between-
Demographic and clinical characteristics with p b 0.1 in the univariate analysis were included in a logistic regression to investigate their unique contributions to variance in psychiatric hospitalization. Variables examined included: age, BD-I subtype, BD-II subtype, suicide attempt, psychosis, ADHD comorbidity, lifetime use of any medication, lifetime use of SGAs, lithium, and SSRI antidepressants. Psychiatric hospitalization served as the dependent variable for this analysis. History of suicide attempt [odds ratio (OR) = 10.4, 95% confidence interval (CI): 2.7–40.7, p = 0.001] and use of SGAs (OR = 7.0, 95% CI: 2.3–21.8, p = 0.001) were significantly associated with psychiatric hospitalization. The associations of psychiatric hospitalization with older age (OR = 1.5, 95% CI: 1.0–2.4, p = 0.05) and psychosis (OR = 3.4, 95% CI: 0.8–14.3, p = 0.095) were reduced to statistical trends. The negative association with BD-II (OR = 0.3, 95% CI: 0.10–1.0, p = 0.05) was also reduced to a statistical trend. Information on primary cause was available for 79 total hospitalizations, representing 45 adolescents with BD. Information was completely or partially missing for 6 participants, accounting for approximately 18 hospitalizations. As information regarding reason for hospitalization relied on chart review and was not ascertained systematically, these data are presented for descriptive purposes and were not subjected to further statistical analysis. According to chart review, mania or psychotic mania was the most common primary cause of hospitalization (35% of cases), followed by suicidal ideation (19%), suicide attempt (18%) and depression (17%). A total of 11% of the hospitalizations were attributable to various other reasons including selfinjurious behavior, aggression, medication misuse or optimization, anxiety, food restriction, and catatonia.
Table 1 Demographic characteristics of 100 adolescents with bipolar disorders (BD) with versus without psychiatric hospitalization.
Age, mean ± SD Socioeconomic status, mean ± SD (n = 96)
Sex (males) Race (white) Intact family b
Overall sample (n = 100)
Psychiatric hospitalization (n = 50)
No psychiatric hospitalization (n = 50)
Statistic a
p
16.2 ± 1.5 48.5 ± 12.9
16.6 ± 1.3 47.9 ± 13.4
15.8 ± 1.5 49.1 ± 12.5
−3.1 0.48
0.003⁎⁎⁎ 0.63
n (%)
n (%)
n (%)
33 (33) 86 (86) 56 (56)
13 (26) 40 (80) 26 (52)
20 (40) 46 (92) 30 (60)
2.2 3.0 0.65
0.14 0.08 0.42
If a variable has n b 100 due to missing information, the actual n value is noted beside the variable. Otherwise, it is assumed that all variables have n = 100. ⁎⁎⁎ p b 0.001. a Two-tailed Pearson χ 2 analyses were performed for categorical variables and two-tailed t-tests conducted for continuous variables. b Subject lives with both biological parents.
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Table 2 Clinical characteristics, comorbidities, medication history, and life events of 100 adolescents with bipolar disorders (BD) with versus without psychiatric hospitalization.
Clinical characteristics BD subtype BD-I BD-II BD-NOS Psychosis Self-injurious behavior Suicidal ideation Suicide attempt Physical or sexual abuse Comorbidity ADHD SUD ODD Conduct disorder Anxiety disorder Panic disorder Medication history Lifetime medication Lifetime antimanic/anticonvulsants b Lifetime 2nd generation antipsychotics c Lifetime lithium Lifetimes SSRI antidepressants d Lifetime non-SSRI antidepressants e Lifetime stimulants f Life events and functioning Police contact or arrest CBQ (parent; high) (n = 94) CALS (parent; high) (n = 90) CALS (adolescent; high) (n = 90) LPI identity confusion (% high) (n = 92) LPI interpersonal chaos (% high) (n = 92) LPI impulsivity (% high) (n = 92) LPI emotional dysregulation (% high) (n = 92)
Statistic a
p
3 (6) 27 (54) 20 (40) 6 (12) 24 (48) 28 (56) 7 (14) 7 (14)
21.3 21.9 9.7 2.8 7.9 0.04 1.1 6.5 0.64
b0.001⁎⁎⁎ b0.001⁎⁎⁎ 0.008⁎⁎ 0.25 0.005⁎⁎ 0.84 0.31 0.01⁎ 0.42
16 (32) 20 (40) 15 (30) 5 (10) 37 (74) 7 (14)
25 (50) 13 (26) 21 (42) 5 (10) 35 (70) 10 (20)
3.3 2.2 1.6 b0.01 0.2 0.6
0.07 0.14 0.21 N0.99 0.66 0.42
(71) (13) (53) (20) (32) (14) (16)
43 (86) 8 (16) 38 (76) 17 (34) 21 (42) 6 (12) 8 (16)
28 (56) 5 (10) 15 (30) 3 (6) 11 (22) 8 (16) 8 (16)
10.9 0.8 21.2 12.3 4.6 0.3 b0.01
0.001⁎⁎ 0.37 b0.001⁎⁎⁎ b0.001⁎⁎⁎ 0.03⁎ 0.56 N0.99
(43) (53) (52) (51) (54) (52) (54) (54)
24 (48) 22 (48) 50 21 (48) 19 (43) 20 (46) 22 (50) 20 (46)
19 28 55 25 31 28 28 30
Overall sample (n = 100), n (%)
Psychiatric hospitalization (n = 100), n (%)
No psychiatric hospitalization (n = 100), n (%)
26 40 34 24 47 61 25 17
(26) (40) (34) (24) (47) (61) (25) (17)
23 (46) 13 (26) 14 (28) 18 (36) 23 (46) 33 (66) 18 (36) 10 (20)
41 33 36 10 72 17
(41) (33) (36) (10) (72) (17)
71 13 53 20 32 14 16 43 50 47 46 50 48 50 50
(38) (58) (54) (65) (58) (58) (63)
1.0 1.0 0.2 0.4 4.2 1.5 0.6 2.7
0.31 0.31 0.60 0.53 0.04⁎ 0.22 0.42 0.1
BD = bipolar disorder; BD-I = bipolar I disorder; BD-II = bipolar II disorder; BD-NOS = bipolar disorder not otherwise specified; ADHD = attention-deficit hyperactivity disorder; SUD = substance use disorder; ODD = oppositional defiant disorder; SSRI = selective serotonin reuptake inhibitor; CBQ = Conflict Behavior Questionnaire; CALS = Children Affective Liability Scale; LPI = Life Problems Inventory. If a variable has n b 100 due to missing information, the actual n value is noted beside the variable. Otherwise, it is assumed that all variables have n = 100. ⁎ p b 0.05. ⁎⁎ p b 0.01. ⁎⁎⁎ p b 0.001. a Two-tailed Pearson χ 2 analyses were performed for categorical variables. b Antimanic anticonvulsants = valproic acid, divalproex, carbamazepine. c Second generation antipsychotics = risperidone, olanzipine, aripiprazole, ziprasidone, seroquel. d SSRI antidepressants = zoloft, paroxetine, prozac, fluvoxamine, citalopram, lexapro. e Non-SSRI antidepressants = wellbutrin, remeron, effexor, cymbalta. f Stimulants = ritalin, concerta, adderall, dexedrine.
4. Discussion This study found that 50% of the Canadian adolescents with BD in our sample had a history of psychiatric hospitalization. The current study is the only one to our knowledge to examine a wide range of correlates of psychiatric hospitalization in Canadian adolescents with BD. We found older age, BD-I, history of attempted suicide, psychosis, lifetime use of SGAs, lithium, SSRI antidepressants and any medication to be positively associated with psychiatric hospitalization, while BD-II was negatively associated with hospitalization. History
of suicide attempt and of exposure to SGAs were the variables most robustly associated with psychiatric hospitalization in multivariable analyses. In descriptive information derived from chart review, nearly 90% of hospitalizations were precipitated by mania, suicidality, or depression without suicidality. This mirrors trends in the literature on adults, such as one study which found mania accounting for 50% of hospitalizations, depression for 25% and mixed episodes for 10% [20], and another that found suicidality accounting for 48%, mania for 27% and depression for 16% [50]. In adolescents, mania
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Table 3 First- and second-degree family history among 100 adolescents with bipolar disorders (BD) with versus without psychiatric hospitalization.
Mania/hypomania MDE ADHD Anxiety SUD
Overall sample (n = 100), n (%)
Psychiatric hospitalization (n = 50), n (%)
No psychiatric hospitalization (n = 50), n (%)
Statistic a
p
53 (53) 78 (78) 28 (28) 54 (54) 45 (45)
30 (60) 39 (78) 13 (26) 29 (58) 23 (46)
23 39 15 25 22
2.0 b0.01 0.2 0.6 0.04
0.16 N0.99 0.66 0.42 0.84
(46) (78) (30) (50) (44)
MDE = major depressive episode; ADHD = attention-deficit hyperactivity disorder; CD = conduct disorder; SUD = substance use disorder. a Two-tailed Pearson χ 2 analyses were performed for categorical variables.
(irritability in particular) has been cited as the most common reason for psychiatric hospitalization [51]. In the current study, 50% of adolescents with BD had a lifetime psychiatric hospitalization, which is somewhat lower than a recent study that found a 63% prevalence [52]. The higher rate of psychiatric hospitalization found in the COBY study may be due to a greater percentage of subjects with BD-I, and/or may relate to aforementioned difference in the American and Canadian healthcare systems. The hospitalization rates in this sample of adolescents were higher than in studies of mixed samples of children and adolescents that have investigated patients with BD-I (41.2%) [53], and patients of all BD subtypes (41.6%) [39], and considerably higher than rates found for children, ages 12 and under, for whom reported rates are closer to 20% [35,51]. Indeed, in the current study of exclusively adolescents we found that older age was associated with increased prevalence of hospitalization. More than 75% of adults with BD report at least one psychiatric hospitalization [5], though prevalence in older patients is at least partially attributable to accumulated opportunity for psychiatric hospitalization. Participants with BD-I were significantly more likely to have a psychiatric hospitalization than those with other BD subtypes. This result is expected, as a criterion for BD-I diagnosis is a manic episode, which is often differentiated from hypomania by the necessity for hospitalization. Indeed, mania was the most common primary cause of psychiatric hospitalization. As follows, participants with BD-II were significantly less likely to have a psychiatric hospitalization than those with other BD subtypes. BD-II has been previously associated with lower hospitalization rates compared to BD-I in adults [21,54], and in a study of a combined sample of children and adolescents [55]. The COBY study in particular found prevalence of psychiatric hospitalization among the combined sample of youth with BD-I, BD-II, and BD-NOS to be 66.1%, 53.3%, and 28.8%, respectively. However, given that more than 50% of hospitalizations were precipitated by depression or suicidality, it appears that there may be other factors at play that are yet unknown. This study found that adolescents with, versus without, a history of suicide attempt(s) were significantly more likely to have a lifetime psychiatric hospitalization. Suicide attempt
was the primary cause of 18% of hospitalizations. This is in line with other research on adolescent BD that finds suicide attempts related to more use of restrictive treatment settings [35]. Psychosis was significantly associated with psychiatric hospitalization. Psychosis has been previously shown to predict psychiatric hospitalization in adults [18], and patients with psychotic BD have been found to experience a first hospitalization at a younger age than individuals with BD and no psychosis [56]. Psychosis can accompany mania, which was responsible for half of the psychiatric hospitalizations in this sample. Adolescents with a history of psychotropic medication use were significantly more likely to have a history of psychiatric hospitalization. Due to the retrospective methodology employed, the present study cannot determine whether medications were initiated prior to, during, or following hospitalization. We found risk for hospitalization to be strongly associated with use of SGAs, which was significant in both the univariate and multivariate analyses. Adults with BD treated with SGAs have been previously shown to be at higher risk for hospitalization [28] compared to those not on SGAs. Lithium use was also significantly associated with lifetime psychiatric hospitalization. We found a significant association between SSRI antidepressant use and psychiatric hospitalization, which has been previously shown in adults [27]. As the current study did not characterize the severity, duration, or number of previous depressive episodes, this finding may be confounded by indication. Indeed, depressive episodes increase risk for hospitalization among adults [12,25]. Previous studies on psychiatric hospitalization in adolescent BD have found significant association with female gender [38,39], although absence of gender difference in hospitalization rates has also been reported [57]. The current study did not find a significant association for gender in regards to psychiatric hospitalization. Males were numerically less likely to have been hospitalized, although this association was not statistically significant. Given that our sample of 100 individuals was comprised of only 33% males, it is possible that our results would have been significant given a larger sample. Finally, the current study found a statistical trend (p = 0.07) toward less psychiatric hospitalizations for BD adolescents with, versus without, comorbid ADHD. A recent
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study found that comorbid ADHD is not associated with increased hospitalizations in children with BD [58]. The need exists for further research on ADHD-BD comorbidity in regards to psychiatric hospitalization. The current study has several limitations. The sample was derived from a sub-specialty clinic in a tertiary hospital, based in a diverse urban environment, and may not be representative of populations using different services or living in different regions. In addition, psychiatric hospitalization was determined based on interviewing adolescents and their parents, and confirmatory hospital records were not systematically reviewed. Information regarding cause of hospitalization was not obtained systematically, which limited the usefulness of the data in statistical analysis. Finally, as this studied employed a cross-sectional, retrospective approach, it could not be determined for most correlates of psychiatric hospitalization whether they served as antecedents or consequences of hospitalization. The current study examined a broad spectrum of variables. Although the multivariable analyses offer some protection against spurious findings, the possibility of type I error remains. Given the importance of the topic and the paucity of available data on this topic, we opted for this approach over a more highly conservative approach.
5. Conclusions Many findings in the current study are congruent with the current literature in the US regarding psychiatric hospitalization in both adolescent and adult BD. The narrowed focus on psychiatric hospitalization is infrequent in the literature, especially in regards to adolescents, and identified several novel correlates that warrant further investigation. Psychiatric hospitalization is often a crisis-oriented intervention that, although often necessary, is also often disruptive to patients and families. Moreover, young patients may be particularly affected by psychiatric hospitalizations due to the impact on the continuity of schooling and of social and recreational activities. Psychiatric hospitalizations are also exceedingly costly to the healthcare system. Taken together, this suggests that identifying strategies to prevent hospitalization may benefit all stakeholders, including patients, families, and the healthcare system. This study identifies a number of characteristics associated with psychiatric hospitalization among Canadian adolescents with BD that, if replicated by others and in prospective samples, may help to inform the development of strategies and practices to reduce the need for psychiatric hospitalization.
[3] [4] [5]
[6]
[7] [8]
[9]
[10]
[11]
[12]
[13]
[14] [15] [16] [17]
[18]
[19]
[20]
[21]
[22]
[23]
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J. Shapiro et al. / Comprehensive Psychiatry 55 (2014) 1855–1861 [25] Lazarus A, Lage M, Pesa J. PMH53 Hospitalization rates during combination therapy with atypical antipsychotics in bipolar disorder. Value Health 2004;7(3):279-80. [26] Kim E, You M, Pikalov A, Van-Tran Q, Jing Y. One-year risk of psychiatric hospitalization and associated treatment costs in bipolar disorder treated with atypical antipsychotics: a retrospective claims database analysis. BMC Psychiatry 2011;11(1):6. [27] Bresnahan B, Ling D, Neslusan C, White A, Wang S, Crown W. The risk of hospitalization for patients with bipolar disorder. Eur Neuropsychopharmacol 2001;11:S210-1. [28] Guo JJ, Keck Jr PE, Li H, Jang R, Kelton CM. Treatment costs and health care utilization for patients with bipolar disorder in a large managed care population. Value Health 2008;11(3):416-23. [29] Pfuntner A, Wier LM, Stocks C. Most frequent conditions in US hospitals, 2010; 2013. [30] Blader JC. Acute inpatient care for psychiatric disorders in the United States, 1996 through 2007. Arch Gen Psychiatry 2011;68(12):1276-83. [31] Blader JC, Carlson GA. Increased rates of bipolar disorder diagnoses among US child, adolescent, and adult inpatients, 1996–2004. Biol Psychiatry 2007;62(2):107-14. [32] Harpaz-Rotem I, Leslie DL, Martin A, Rosenheck RA. Changes in child and adolescent inpatient psychiatric admission diagnoses between 1995 and 2000. Soc Psychiatry Psychiatr Epidemiol 2005;40(8):642-7. [33] Olfson M, Gameroff MJ, Marcus SC, Greenberg T, Shaffer D. National trends in hospitalization of youth with intentional self-inflicted injuries. Am J Psychiatr 2005;162(7):1328-35. [34] Peele PB, Axelson DA, Xu Y, Malley EE. Use of medical and behavioral health services by adolescents with bipolar disorder. Psychiatr Serv 2004;55(12):1392-6. [35] Mendenhall AN, Demeter C, Findling RL, Frazier TW, Fristad MA, Youngstrom EA, et al. Factors influencing mental health service utilization by children with serious emotional and behavioral disturbance: results from the LAMS study. Psychiatr Serv 2011;62(6):650-8. [36] Mendenhall AN. Predictors of service utilization among youth diagnosed with mood disorders. J Child Fam Stud 2012;21(4):603-11. [37] Wozniak J, Spencer T, Biederman J, Kwon A, Monuteaux M, Rettew J, et al. The clinical characteristics of unipolar vs. bipolar major depression in ADHD youth. J Affect Disord 2004;82:S59-69. [38] Rizzo CJ, Esposito-Smythers C, Swenson L, Birmaher B, Ryan N, Strober M, et al. Factors associated with mental health service utilization among bipolar youth. Bipolar Disord 2007;9(8):839-50. [39] Evans-Lacko SE, Spencer CS, Logan JE, Riley AW. Patterns and predictors of restrictive health care service use by youths with bipolar disorder. Adm Policy Ment Health Ment Health Serv Res 2010;37(5):379-87. [40] Katz SJ, Kessler RC, Frank RG, Leaf P, Lin E. Mental health care use, morbidity, and socioeconomic status in the United States and Ontario. Inquiry 1997:38-49. [41] Vasiliadis H-M, Lesage A, Adair C, Wang P, Kessler R. Do Canada and the United States differ in prevalence of depression and utilization of services? Psychiatr Serv 2007;58(1):63-71. [42] Katz SJ, Kessler RC, Lin E, Wells KB. Medication management of depression in the United States and Ontario. J Gen Intern Med 1998;13 (2):77-85. [43] Kaufman J, Birmaher B, Brent D, Rao U, Flynn C, Moreci P, et al. Schedule for affective disorders and schizophrenia for school-age children-present and lifetime version (K-SADS-PL): initial reliability
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ScienceDirect Comprehensive Psychiatry 55 (2014) 1855 – 1861 www.elsevier.com/locate/comppsych
Correlates of psychiatric hospitalization in a clinical sample of Canadian adolescents with bipolar disorder Joshua Shapiro a, b , Vanessa Timmins a , Brenda Swampillai a , Antonette Scavone a , Katelyn Collinger a , Carolyn Boulos a , Jessica Hatch a , Benjamin I. Goldstein a,⁎ a
Department of Psychiatry, Sunnybrook Health Sciences Centre, Toronto, ON, Canada b Wilfrid Laurier University, Waterloo, ON, Canada
Abstract Objective: To identify factors associated with psychiatric hospitalization among adolescents with bipolar disorder (BD). Methods: Participants were 100 adolescents, ages 13–19, who fulfilled DSM-IV criteria for bipolar I disorder [(BD-I), n = 26], bipolar II disorder [(BD-II), n = 40], or operationalized criteria for BD not otherwise specified [(BD-NOS), n = 34], via the Schedule for Affective Disorders and Schizophrenia, Present and Lifetime version (KSADS-PL). Demographic, clinical, and family history variables were measured via clinical interview with the participant and a parent or guardian. Results: The lifetime prevalence of psychiatric hospitalization was 50%. Significant predictors of psychiatric hospitalization in univariate analyses included older age, BD-I, history of suicide attempt, psychosis, lifetime use of second generation antipsychotics (SGAs), lithium, SSRI antidepressants and any medication. BD-II was negatively associated with psychiatric hospitalization. In multivariable analyses, older age, history of suicide attempt, psychosis and use of SGAs were positively associated with hospitalization, whereas BD-II was negatively associated with hospitalization. Conclusions: Psychiatric hospitalization in adolescents with BD is highly prevalent and associated with older age and proxies for greater illness severity. Further studies are needed to identify strategies for reducing the need for psychiatric hospitalizations among adolescents with BD. © 2014 Elsevier Inc. All rights reserved.
1. Introduction Bipolar disorder (BD) is a recurrent and impairing illness that is associated with substantial burden of mood symptoms and comorbidity among adults and youth [1–3]. BD often requires high treatment usage [4], and more than 75% of adults with BD report one or more lifetime psychiatric hospitalizations [5]. With widespread decreases in the number of psychiatric beds, psychiatric hospitalization in recent years is often precipitated by acute crises that necessitate hospitalization for the purpose of risk containment. As such, psychiatric hospitalization is often a decision driven by immediate need rather than individual preferences among patients, families,
⁎ Corresponding author at: Centre for Youth Bipolar Disorder, Sunnybrook Health Sciences Centre; 2075 Bayview Ave., Room FG-53. Tel.: +1 416 480 5328. E-mail address: [email protected] (B.I. Goldstein). http://dx.doi.org/10.1016/j.comppsych.2014.08.048 0010-440X/© 2014 Elsevier Inc. All rights reserved.
and/or practitioners. Concerns about hospitalization relate to the disruptive and distressing experience psychiatric hospitalization can be for patients with BD and their families, and the substantial costs incurred [6,7]. The overall treatment costs of patients with BD have been found to exceed those for other behavioral and mood disorders [8–10], a disparity that is attributable in large part to hospitalizations which account for 20% of these costs [11]. Investigation of clinical characteristics associated with hospitalization can potentially help align outpatient treatment focus toward preventing these outcomes and identify patients at risk for hospitalization. Hospitalizations among adults with BD have been associated with substance use disorders (SUD) [12–15], rapid cycling [16,17], psychosis [18], previous hospitalization [19,20], BD-I subtype [21], female gender [22,23], various medications [11,16–18,24–28], minority status [18], polypharmacy [27], and marital separation [13]. While there is a larger literature on this topic among adults with BD, there is a growing body of literature regarding the rates and correlates of psychiatric hospitalization among
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adolescents with BD. Hospitalization rates for psychiatric disorders in youth, especially BD, have increased markedly in the past 20 years [29–33]. The annual rate of hospitalization among adolescents with BD in the US was found to be 39.6% in 2003 [8]. Annual rates in children and adolescents increased 434% between 1997 and 2010 [29], which coincided with a large increase in number of BD diagnoses for this age group [30,31]. Adolescents with BD are hospitalized more often than those with most other psychiatric and behavioral disorders [34–37], and rates of inpatient service use now exceed even those of adults with BD in some reports [22]. Female gender [38,39], comorbid health conditions [39] and having a parent with SUD [38] have all been shown to be directly associated with hospitalization in adolescents with BD, while suicidal or self-injurious behavior [35], comorbid physical conditions in general [39] and rapid cycling [38] are associated with use of highly restrictive treatment settings. The purpose of this report is to expand the literature on mental health service use among adolescents with BD by investigating characteristics associated with psychiatric hospitalization in a treatment-seeking sample from a subspecialty clinic at a tertiary academic health sciences center in Canada. Most previous studies on the topic of psychiatric hospitalizations among youth with BD are derived from American populations, and differences in the two nations' health care systems [40,41] suggest the need to examine this topic among Canadian adolescents specifically. In particular, the absence of universal healthcare to date may render barriers that are not present in socialized healthcare [42], which may cause for differences in factors associated with psychiatric hospitalization.
2. Methods 2.1. Sample and setting The present study includes 100 participants, ages 13–19, with BD-I (n = 26), BD-II (n = 40), or BD-not otherwise specified (NOS; n = 34). Participants were seeking outpatient assessment and/or treatment at a sub-specialty clinic in a tertiary academic health sciences center. Written informed consent was provided by parent(s) and adolescent before study commencement. Research ethics board approval was obtained. At least one parent/guardian for each adolescent also participated. 2.2. Subject assessment Diagnoses (current and lifetime) were determined via the Schedule for Affective Disorders and Schizophrenia, Present and Lifetime version (KSADS-PL) [43], which incorporates information from adolescents and their parent(s). Similarly, lifetime history of psychiatric hospitalization was ascertained during the KSADS-PL interview. Primary cause of hospitalization was determined through review of available patient charts. All interviewers had a bachelor's or master's
degree in a mental health field and completed comprehensive KSADS training under the supervision of the senior author (B.G.). The KSADS Depression Rating Scale (DEP-P) [44] and KSADS Mania Rating Scale (MRS) [45] were used in place of the mood sections of the KSADS-PL. Diagnoses were determined with the consideration of all available information and clinical judgment was used when conflicting information was provided. Diagnoses were confirmed by a consensus meeting with a child psychiatrist following completion of the KSADS-PL interview (B.G.). This study employed operationalized criteria for BD-NOS as described in the Course and Outcome of Bipolar Youth (COBY) study [46]: elevated and/or irritable mood, plus (i) two DSM-IV manic symptoms (three if only irritable mood is reported), (ii) change in functioning, (iii) mood and symptom duration of at least 4 h during a 24-h period, and (iv) at least four cumulative 24-h periods of episodes over the participant's lifetime that meet the mood, symptom severity, and functional change criteria. The age of onset of an individual's BD was considered to be when the participant first met DSM-IV criteria for a manic, hypomanic, or major depressive episode, or when he/she first met study criteria for BD-NOS. A self-reported medical history questionnaire and the post-traumatic stress disorder (PTSD) screen within the KSADS-PL were used to obtain history of physical and sexual abuse. A Safety Assessment Form, an intervieweradministered questionnaire, was used to determine lifetime aggression and suicidality that may have occurred outside of the context of a depressive episode. The Conflict Behavior Questionnaire (CBQ) self-report assesses family conflict and was completed by parents regarding their adolescent [47]. Psychiatric status and history of first- and second-degree relatives was obtained through an interview with the adolescent and parent(s), using the Family History Screen [48]. Socioeconomic status was determined via the 4-factor Hollingshead Scale [49]. 2.3. Data analysis Variables were screened for their association with lifetime psychiatric hospitalization using chi-square tests for categorical variables and t-tests for continuous variables. For the purpose of this analysis, the dimensional CBQ, LPI and CALS questionnaires were dichotomized as high score versus low score on the basis of a median split. Demographic and clinical characteristics and comorbidities that were associated with psychiatric hospitalization (p b 0.1) in the univariate analyses were entered into a backward elimination Wald logistic regression model in order to examine the unique contribution to variance in psychiatrics hospitalizations associated with each predictor, controlling for the effects of other predictors. All p values are based on two-tailed tests with a significance level of α = 0.05. Statistical correction for multiple comparisons was not applied as information on the correlates of psychiatric hospitalization in this population is scarce,
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especially since youth with BD-II and BD-NOS were included. The Statistical Package for the Social Sciences Version 20 (SPSS) was used to perform statistical analyses.
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group differences in prevalence of these familial conditions were observed. 3.3. Logistic regression analysis
3. Results 3.1. Socio-demographic characteristics of adolescents with bipolar disorder who had a psychiatric hospitalization Socio-demographic characteristics of all participants are portrayed in Table 1. Of the 100 adolescents with BD, 50% had at least one lifetime psychiatric hospitalization. Participants with, versus without, a history of psychiatric hospitalization were significantly older. Gender, race, socioeconomic status and living with both natural parents were not significantly associated with psychiatric hospitalization. 3.2. Clinical and familial characteristics of adolescents with bipolar disorder who had a psychiatric hospitalization A comparison of clinical characteristics distinguishing those who have a lifetime psychiatric hospitalization to those who have not is portrayed in Table 2. BD subtype was significantly associated with psychiatric hospitalization. A post-hoc univariate analysis of the three BD subtypes revealed that patients with BD-I were significantly more likely to have a psychiatric hospitalization, while patients with BD-II were significantly less likely. Participants with, versus without, lifetime psychiatric hospitalization were significantly more likely to have lifetime psychosis, lifetime suicide attempt, and trended toward lower prevalence of comorbid attention deficit hyperactivity disorder (ADHD) (p = 0.07). Participants with lifetime psychiatric hospitalization were also significantly more likely to have lifetime use of lithium, SSRI antidepressants, second generation antipsychotics (SGAs) and any medication. First- and second- degree family history of mania or hypomania, major depressive episode, ADHD, conduct disorder, anxiety and substance dependence is displayed in Table 3. No significant between-
Demographic and clinical characteristics with p b 0.1 in the univariate analysis were included in a logistic regression to investigate their unique contributions to variance in psychiatric hospitalization. Variables examined included: age, BD-I subtype, BD-II subtype, suicide attempt, psychosis, ADHD comorbidity, lifetime use of any medication, lifetime use of SGAs, lithium, and SSRI antidepressants. Psychiatric hospitalization served as the dependent variable for this analysis. History of suicide attempt [odds ratio (OR) = 10.4, 95% confidence interval (CI): 2.7–40.7, p = 0.001] and use of SGAs (OR = 7.0, 95% CI: 2.3–21.8, p = 0.001) were significantly associated with psychiatric hospitalization. The associations of psychiatric hospitalization with older age (OR = 1.5, 95% CI: 1.0–2.4, p = 0.05) and psychosis (OR = 3.4, 95% CI: 0.8–14.3, p = 0.095) were reduced to statistical trends. The negative association with BD-II (OR = 0.3, 95% CI: 0.10–1.0, p = 0.05) was also reduced to a statistical trend. Information on primary cause was available for 79 total hospitalizations, representing 45 adolescents with BD. Information was completely or partially missing for 6 participants, accounting for approximately 18 hospitalizations. As information regarding reason for hospitalization relied on chart review and was not ascertained systematically, these data are presented for descriptive purposes and were not subjected to further statistical analysis. According to chart review, mania or psychotic mania was the most common primary cause of hospitalization (35% of cases), followed by suicidal ideation (19%), suicide attempt (18%) and depression (17%). A total of 11% of the hospitalizations were attributable to various other reasons including selfinjurious behavior, aggression, medication misuse or optimization, anxiety, food restriction, and catatonia.
Table 1 Demographic characteristics of 100 adolescents with bipolar disorders (BD) with versus without psychiatric hospitalization.
Age, mean ± SD Socioeconomic status, mean ± SD (n = 96)
Sex (males) Race (white) Intact family b
Overall sample (n = 100)
Psychiatric hospitalization (n = 50)
No psychiatric hospitalization (n = 50)
Statistic a
p
16.2 ± 1.5 48.5 ± 12.9
16.6 ± 1.3 47.9 ± 13.4
15.8 ± 1.5 49.1 ± 12.5
−3.1 0.48
0.003⁎⁎⁎ 0.63
n (%)
n (%)
n (%)
33 (33) 86 (86) 56 (56)
13 (26) 40 (80) 26 (52)
20 (40) 46 (92) 30 (60)
2.2 3.0 0.65
0.14 0.08 0.42
If a variable has n b 100 due to missing information, the actual n value is noted beside the variable. Otherwise, it is assumed that all variables have n = 100. ⁎⁎⁎ p b 0.001. a Two-tailed Pearson χ 2 analyses were performed for categorical variables and two-tailed t-tests conducted for continuous variables. b Subject lives with both biological parents.
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Table 2 Clinical characteristics, comorbidities, medication history, and life events of 100 adolescents with bipolar disorders (BD) with versus without psychiatric hospitalization.
Clinical characteristics BD subtype BD-I BD-II BD-NOS Psychosis Self-injurious behavior Suicidal ideation Suicide attempt Physical or sexual abuse Comorbidity ADHD SUD ODD Conduct disorder Anxiety disorder Panic disorder Medication history Lifetime medication Lifetime antimanic/anticonvulsants b Lifetime 2nd generation antipsychotics c Lifetime lithium Lifetimes SSRI antidepressants d Lifetime non-SSRI antidepressants e Lifetime stimulants f Life events and functioning Police contact or arrest CBQ (parent; high) (n = 94) CALS (parent; high) (n = 90) CALS (adolescent; high) (n = 90) LPI identity confusion (% high) (n = 92) LPI interpersonal chaos (% high) (n = 92) LPI impulsivity (% high) (n = 92) LPI emotional dysregulation (% high) (n = 92)
Statistic a
p
3 (6) 27 (54) 20 (40) 6 (12) 24 (48) 28 (56) 7 (14) 7 (14)
21.3 21.9 9.7 2.8 7.9 0.04 1.1 6.5 0.64
b0.001⁎⁎⁎ b0.001⁎⁎⁎ 0.008⁎⁎ 0.25 0.005⁎⁎ 0.84 0.31 0.01⁎ 0.42
16 (32) 20 (40) 15 (30) 5 (10) 37 (74) 7 (14)
25 (50) 13 (26) 21 (42) 5 (10) 35 (70) 10 (20)
3.3 2.2 1.6 b0.01 0.2 0.6
0.07 0.14 0.21 N0.99 0.66 0.42
(71) (13) (53) (20) (32) (14) (16)
43 (86) 8 (16) 38 (76) 17 (34) 21 (42) 6 (12) 8 (16)
28 (56) 5 (10) 15 (30) 3 (6) 11 (22) 8 (16) 8 (16)
10.9 0.8 21.2 12.3 4.6 0.3 b0.01
0.001⁎⁎ 0.37 b0.001⁎⁎⁎ b0.001⁎⁎⁎ 0.03⁎ 0.56 N0.99
(43) (53) (52) (51) (54) (52) (54) (54)
24 (48) 22 (48) 50 21 (48) 19 (43) 20 (46) 22 (50) 20 (46)
19 28 55 25 31 28 28 30
Overall sample (n = 100), n (%)
Psychiatric hospitalization (n = 100), n (%)
No psychiatric hospitalization (n = 100), n (%)
26 40 34 24 47 61 25 17
(26) (40) (34) (24) (47) (61) (25) (17)
23 (46) 13 (26) 14 (28) 18 (36) 23 (46) 33 (66) 18 (36) 10 (20)
41 33 36 10 72 17
(41) (33) (36) (10) (72) (17)
71 13 53 20 32 14 16 43 50 47 46 50 48 50 50
(38) (58) (54) (65) (58) (58) (63)
1.0 1.0 0.2 0.4 4.2 1.5 0.6 2.7
0.31 0.31 0.60 0.53 0.04⁎ 0.22 0.42 0.1
BD = bipolar disorder; BD-I = bipolar I disorder; BD-II = bipolar II disorder; BD-NOS = bipolar disorder not otherwise specified; ADHD = attention-deficit hyperactivity disorder; SUD = substance use disorder; ODD = oppositional defiant disorder; SSRI = selective serotonin reuptake inhibitor; CBQ = Conflict Behavior Questionnaire; CALS = Children Affective Liability Scale; LPI = Life Problems Inventory. If a variable has n b 100 due to missing information, the actual n value is noted beside the variable. Otherwise, it is assumed that all variables have n = 100. ⁎ p b 0.05. ⁎⁎ p b 0.01. ⁎⁎⁎ p b 0.001. a Two-tailed Pearson χ 2 analyses were performed for categorical variables. b Antimanic anticonvulsants = valproic acid, divalproex, carbamazepine. c Second generation antipsychotics = risperidone, olanzipine, aripiprazole, ziprasidone, seroquel. d SSRI antidepressants = zoloft, paroxetine, prozac, fluvoxamine, citalopram, lexapro. e Non-SSRI antidepressants = wellbutrin, remeron, effexor, cymbalta. f Stimulants = ritalin, concerta, adderall, dexedrine.
4. Discussion This study found that 50% of the Canadian adolescents with BD in our sample had a history of psychiatric hospitalization. The current study is the only one to our knowledge to examine a wide range of correlates of psychiatric hospitalization in Canadian adolescents with BD. We found older age, BD-I, history of attempted suicide, psychosis, lifetime use of SGAs, lithium, SSRI antidepressants and any medication to be positively associated with psychiatric hospitalization, while BD-II was negatively associated with hospitalization. History
of suicide attempt and of exposure to SGAs were the variables most robustly associated with psychiatric hospitalization in multivariable analyses. In descriptive information derived from chart review, nearly 90% of hospitalizations were precipitated by mania, suicidality, or depression without suicidality. This mirrors trends in the literature on adults, such as one study which found mania accounting for 50% of hospitalizations, depression for 25% and mixed episodes for 10% [20], and another that found suicidality accounting for 48%, mania for 27% and depression for 16% [50]. In adolescents, mania
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Table 3 First- and second-degree family history among 100 adolescents with bipolar disorders (BD) with versus without psychiatric hospitalization.
Mania/hypomania MDE ADHD Anxiety SUD
Overall sample (n = 100), n (%)
Psychiatric hospitalization (n = 50), n (%)
No psychiatric hospitalization (n = 50), n (%)
Statistic a
p
53 (53) 78 (78) 28 (28) 54 (54) 45 (45)
30 (60) 39 (78) 13 (26) 29 (58) 23 (46)
23 39 15 25 22
2.0 b0.01 0.2 0.6 0.04
0.16 N0.99 0.66 0.42 0.84
(46) (78) (30) (50) (44)
MDE = major depressive episode; ADHD = attention-deficit hyperactivity disorder; CD = conduct disorder; SUD = substance use disorder. a Two-tailed Pearson χ 2 analyses were performed for categorical variables.
(irritability in particular) has been cited as the most common reason for psychiatric hospitalization [51]. In the current study, 50% of adolescents with BD had a lifetime psychiatric hospitalization, which is somewhat lower than a recent study that found a 63% prevalence [52]. The higher rate of psychiatric hospitalization found in the COBY study may be due to a greater percentage of subjects with BD-I, and/or may relate to aforementioned difference in the American and Canadian healthcare systems. The hospitalization rates in this sample of adolescents were higher than in studies of mixed samples of children and adolescents that have investigated patients with BD-I (41.2%) [53], and patients of all BD subtypes (41.6%) [39], and considerably higher than rates found for children, ages 12 and under, for whom reported rates are closer to 20% [35,51]. Indeed, in the current study of exclusively adolescents we found that older age was associated with increased prevalence of hospitalization. More than 75% of adults with BD report at least one psychiatric hospitalization [5], though prevalence in older patients is at least partially attributable to accumulated opportunity for psychiatric hospitalization. Participants with BD-I were significantly more likely to have a psychiatric hospitalization than those with other BD subtypes. This result is expected, as a criterion for BD-I diagnosis is a manic episode, which is often differentiated from hypomania by the necessity for hospitalization. Indeed, mania was the most common primary cause of psychiatric hospitalization. As follows, participants with BD-II were significantly less likely to have a psychiatric hospitalization than those with other BD subtypes. BD-II has been previously associated with lower hospitalization rates compared to BD-I in adults [21,54], and in a study of a combined sample of children and adolescents [55]. The COBY study in particular found prevalence of psychiatric hospitalization among the combined sample of youth with BD-I, BD-II, and BD-NOS to be 66.1%, 53.3%, and 28.8%, respectively. However, given that more than 50% of hospitalizations were precipitated by depression or suicidality, it appears that there may be other factors at play that are yet unknown. This study found that adolescents with, versus without, a history of suicide attempt(s) were significantly more likely to have a lifetime psychiatric hospitalization. Suicide attempt
was the primary cause of 18% of hospitalizations. This is in line with other research on adolescent BD that finds suicide attempts related to more use of restrictive treatment settings [35]. Psychosis was significantly associated with psychiatric hospitalization. Psychosis has been previously shown to predict psychiatric hospitalization in adults [18], and patients with psychotic BD have been found to experience a first hospitalization at a younger age than individuals with BD and no psychosis [56]. Psychosis can accompany mania, which was responsible for half of the psychiatric hospitalizations in this sample. Adolescents with a history of psychotropic medication use were significantly more likely to have a history of psychiatric hospitalization. Due to the retrospective methodology employed, the present study cannot determine whether medications were initiated prior to, during, or following hospitalization. We found risk for hospitalization to be strongly associated with use of SGAs, which was significant in both the univariate and multivariate analyses. Adults with BD treated with SGAs have been previously shown to be at higher risk for hospitalization [28] compared to those not on SGAs. Lithium use was also significantly associated with lifetime psychiatric hospitalization. We found a significant association between SSRI antidepressant use and psychiatric hospitalization, which has been previously shown in adults [27]. As the current study did not characterize the severity, duration, or number of previous depressive episodes, this finding may be confounded by indication. Indeed, depressive episodes increase risk for hospitalization among adults [12,25]. Previous studies on psychiatric hospitalization in adolescent BD have found significant association with female gender [38,39], although absence of gender difference in hospitalization rates has also been reported [57]. The current study did not find a significant association for gender in regards to psychiatric hospitalization. Males were numerically less likely to have been hospitalized, although this association was not statistically significant. Given that our sample of 100 individuals was comprised of only 33% males, it is possible that our results would have been significant given a larger sample. Finally, the current study found a statistical trend (p = 0.07) toward less psychiatric hospitalizations for BD adolescents with, versus without, comorbid ADHD. A recent
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study found that comorbid ADHD is not associated with increased hospitalizations in children with BD [58]. The need exists for further research on ADHD-BD comorbidity in regards to psychiatric hospitalization. The current study has several limitations. The sample was derived from a sub-specialty clinic in a tertiary hospital, based in a diverse urban environment, and may not be representative of populations using different services or living in different regions. In addition, psychiatric hospitalization was determined based on interviewing adolescents and their parents, and confirmatory hospital records were not systematically reviewed. Information regarding cause of hospitalization was not obtained systematically, which limited the usefulness of the data in statistical analysis. Finally, as this studied employed a cross-sectional, retrospective approach, it could not be determined for most correlates of psychiatric hospitalization whether they served as antecedents or consequences of hospitalization. The current study examined a broad spectrum of variables. Although the multivariable analyses offer some protection against spurious findings, the possibility of type I error remains. Given the importance of the topic and the paucity of available data on this topic, we opted for this approach over a more highly conservative approach.
5. Conclusions Many findings in the current study are congruent with the current literature in the US regarding psychiatric hospitalization in both adolescent and adult BD. The narrowed focus on psychiatric hospitalization is infrequent in the literature, especially in regards to adolescents, and identified several novel correlates that warrant further investigation. Psychiatric hospitalization is often a crisis-oriented intervention that, although often necessary, is also often disruptive to patients and families. Moreover, young patients may be particularly affected by psychiatric hospitalizations due to the impact on the continuity of schooling and of social and recreational activities. Psychiatric hospitalizations are also exceedingly costly to the healthcare system. Taken together, this suggests that identifying strategies to prevent hospitalization may benefit all stakeholders, including patients, families, and the healthcare system. This study identifies a number of characteristics associated with psychiatric hospitalization among Canadian adolescents with BD that, if replicated by others and in prospective samples, may help to inform the development of strategies and practices to reduce the need for psychiatric hospitalization.
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