Addictive Behaviors 45 (2015) 281–286
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Addictive Behaviors
Health service utilization of heroin abusers: A retrospective cohort study I-Ming Chen a,b, Charles Lung-Cheng Huang c,d, Bao-Juan Yeh e, Yi-Ling Chien a,f,⁎ a
Department of Psychiatry, National Taiwan University Hospital, Taiwan Institute of Health Policy and Management, College of Public Health, National Taiwan University, Taiwan c Department of Psychiatry, Chi Mei Medical Center, Taiwan d Department of Social Worker, Chia Nan University of Pharmacy and Science, Taiwan e Department of Psychiatry, National Taiwan University Hospital Yun-Lin Branch, Taiwan f Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taiwan b
H I G H L I G H T S • Heroin abusers utilized more emergency services but fewer hospital admissions. • The service utilized was mostly for blood-borne/local infection and traumatic injury. • The major correlates of service utilization were HIV status and education levels.
a r t i c l e
i n f o
Available online 12 February 2015 Keywords: Heroin abuse Medical utilization Somatic diseases Viral hepatitis Human immunodeficiency virus
a b s t r a c t Aims: This study aimed to determine the patterns of medical service utilization among heroin users and to identify the factors associated with the frequency of utilization. Methods: We conducted a retrospective/prospective cohort study of 789 heroin-using adults in a catchment area, collecting data on their usage of medical care, including inpatient care, emergency visits, and outpatient care, in a 2-year observation period. We interviewed and reviewed the medical records of 789 heroin users in a methadone clinic of a general hospital in a rural area of Taiwan. The demographic data, records of service use, diagnoses, and information on viral infection status from Jan. 1, 2007 to Dec. 31, 2008 were collected. Most patients were middle-aged and unemployed, had a basic educational level, and began their first heroin use in their twenties. Results: The health service utilization of heroin users was mostly for infectious diseases, orthopedic conditions, and gastroenterological disorders mainly due to blood-borne or local infections and traumatic injury. Heroin users utilize fewer outpatient or inpatient services, but more emergency care than the general public. The major correlates of inpatient and emergency service utilization were HIV status and education level. Conclusions: Our findings suggest that integrated outpatient services may help to enhance medical service accessibility and adherence, and also imply the necessity of putting more effort into promoting health management and safe behaviors in heroin users, particularly the lower-educated addicts. © 2015 Elsevier Ltd. All rights reserved.
1. Introduction Opioid dependence is a chronic relapsing disorder characterized by high morbidity and premature mortality (Darke, Kaye, & Duflou, 2006; Hser, Hoffman, Grella, & Anglin, 2001), especially when the opioids are abused intravenously. Needle sharing and their sexual practices Abbreviations: AIDS, acquired immunodeficiency syndrome; HBV, hepatitis B virus; HCV, hepatitis C virus; HIV, human immunodeficiency virus; MMT, methadone maintenance therapy ⁎ Corresponding author at: Department of Psychiatry, National Taiwan University Hospital, No.7 Chung San South Road, Taipei, Taiwan. Tel.: +886 2 23123456x66013; fax: +886 2 23825646. E-mail address: [email protected] (Y.-L. Chien).
http://dx.doi.org/10.1016/j.addbeh.2015.01.042 0306-4603/© 2015 Elsevier Ltd. All rights reserved.
place heroin users at high risk of human immunodeficiency virus (HIV) infection, viral hepatitis, and other infectious diseases (Garfein, Vlahov, Galai, Doherty, & Nelson, 1996), as well as a range of medical morbidities (Michaud, Murray, & Bloom, 2001; Sadock, Kaplan, & Sadock, 2007). Despite the high prevalence of comorbidities and an apparent need of medical services, patients with identified drug abuse problems do not receive adequate medical care (D'Aunno & Vaughn, 1995; Saitz, Mulvey, & Samet, 1997), and often delay treatment until their medical problems worsen, which further increases the cost of care (Gelberg, Gallagher, Andersen, & Koegel, 1997; McCoy, Metsch, Chitwood, & Miles, 2001). Nearly half of heroin users presenting at a public hospital needed care for bacterial infections, and 22% for HIV/hepatitis, with the
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majority (72%) requiring admission (Masson et al., 2002). It has also been reported that injection drug users have extremely high rates of emergency department visits (Laine et al., 2001; McGeary & French, 2001; Selwyn, Budner, Wasserman, & Arno, 1993). Evidence from another study also revealed that the social consequences of substance abuse included an increase in medical expenditures for emergency department care and hospitalizations (McGeary & French, 2001). The health service utilization of heroin abusers has been surveyed in Western countries. A comprehensive review by Stein pointed out that injection drug users are at risk of coexisting morbidities including overdoses, soft tissue infections, endocarditis, pulmonary diseases, hepatitis, and sexually transmitted diseases (Stein, 1999). Skeie et al. showed that the most common disease events were injuries, acute local infections, non-fatal overdoses, and infections during methadone maintenance therapy (MMT) (Skeie, Brekke, Lindbaek, & Waal, 2008). In Taiwan, heroin has become one of the most widely used psychoactive substances. Of the 1582 drug abuse events reported by nationwide mental health services in April 2012, 69.5% involved heroin (Food and Drug Administration, Taiwan, 2014). Relevant health problems, such as infection, have been investigated in only a few studies. For example, the seroprevalence rates of HIV antibodies, hepatitis C virus (HCV) antibodies, and hepatitis B virus (HBV) surface antigens among Taiwanese injection heroin users were 25.5%, 89.6%, and 16.7%, respectively (Chu, Chiang, Su, Chang, & Cheng, 2009). In response to the HIV epidemic, the government of Taiwan implemented a comprehensive harm reduction program targeting intravenous drug users in 2005 (Centers for Disease Control R.O.C., Taiwan, 2005), including MMT, needle and syringe exchange, health education and free antiretroviral treatment for HIV infection. The Yunlin government in central Taiwan launched a harm-reduction program in July 2006. A study examining the mortality risk among a cohort of 1616 heroin users in this program between October 2006 and December 2008 found that 26 (1.6%) people had died, with an all-cause mortality rate per 100 person years of 3.42 (Huang & Lee, 2013), suggesting a high rate of mortality. However, the pattern of morbidities and the health service utilization lack research. A systemic evaluation of the type of services needed is required. We therefore conducted a retrospective cohort study of 789 subjects who visited the MMT clinic and analyzed the health service utilization during a 2-year observation period. The objective of the present research was to elucidate the health care demands and medical care utilization of heroin abusers, that may enable us to improve health services accessibility and quality in this population. 2. Methods 2.1. Geographic information and medical system This study was implemented in a general hospital with a 1108-bed inpatient facility. The hospital is located in the political and business center of Yunlin County, an agricultural district with an area of 1290 km2 and 735,000 inhabitants. Patients can visit the hospital with full access to all medical subspecialties with or without referral. The hospital is the main provider of outpatient services, and is the only hospital to provide inpatient and emergency services in Douliou City, the administrative center of Yunlin County, in the study period. All patients who come to the hospital have national health insurance which covers most of their medical expenses. 2.2. Methadone maintenance therapy and study subjects From October 9, 2006 to December 31, 2008, a total of 789 patients participated in the MMT program at our psychiatric clinic. More than 90% of those who underwent MMT were injection heroin abusers (Huang & Lee, 2013). The DSM-IV diagnosis of opioid dependence was made by board-certificated psychiatrists via face-to-face interview.
Most of the heroin abusers (n = 520, 65.9%) voluntarily attended MMT. Among them, 343 patients (43.5%) self-paid for MMT services and 177 (22.4%) got reimbursement from the Centers for Disease of Control because of a diagnosis of HIV infection. Some patients in the latter group were referred from the acquired immunodeficiency syndrome (AIDS) clinic in the hospital, in accordance with the national health policy of the AIDS harm-reduction program. Other patients (n = 269, 34.1%) were mandatorily referred from the criminal justice system in exchange for deferred indictment for illicit drug abuse. The medical costs of MMT and anti-retroviral treatment for HIV-positive patients were totally reimbursed by the government. The HIV-negative group had to pay a part of the outpatient treatment expenses on their own, which was much less expensive than ordinary patients. 2.3. Case manager system and laboratory examinations A case manager was in charge of optimizing treatment adherence. All subjects received routine laboratory examinations including complete blood count, liver and renal function tests, HBV surface antigen, HCV and HIV antibodies on the first visit. For those who had positive results for viral hepatitis or HIV infection, the case manager would ensure further medical treatment by infectious disease or hepatology specialists. 2.4. Data collection and analysis The study was proved by the Research Ethics Committee of National Taiwan University Hospital before its implementation. All the participants completed informed consent after the study procedure was fully explained. The demographic data of the subjects were collected from interviews and medical records. To investigate the medical utilization of heroin abusers, we retrieved electronic records of inpatient, outpatient, and emergency department through the hospital administrative database from Jan. 1, 2007 to Dec. 31, 2008. The frequency of emergency visits, hospitalization, and outpatient clinic visits was counted by a research assistant and double-checked by the corresponding author. The services utilization was then categorized into psychiatric and nonpsychiatric service use for further comparisons. In an effort to clarify the reasons for admission, we retrospectively reviewed the main discharge diagnoses for each hospitalization. Afterward these discharge diagnoses were allotted to corresponding disease categories, which included infectious disease, orthopedics, gastroenterology, psychiatry, gynecology/obstetrics, cardiovascular disease, endocrinology, pulmonology, nephrology, plastic surgery, otolaryngology, cardiac and vascular surgery, neurosurgery, general medicine, general surgery, neurology, hematology, and thoracic surgery. The most frequent diagnoses as well as the most severe ones were counted. 2.5. Predicted health service utilization estimated by nationwide annual statistics To compare the health service utilization of heroin abusers to the general population of the nation, we retrieved the nationwide annual statistics of health services claimed during 2007 and 2008 (Table 1) from the public database (Ministry of Health and Welfare, Taiwan, 2013), and estimated the service utilization for each sex and age group, which was then standardized by the sex and age distribution of our cohort. 2.6. Statistical analysis A substantial portion of the cohort frequently visited the EmergencyDepartment (ED) and outpatient clinic, or had been repeatedly admitted. In the interest of studying the pattern of medical service
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Table 1 The nationwide annual statistics of health services claimed during 2007 and 2008, from age 15 to 69 years for each gender. Outpatient services Psychiatric
Inpatient services Non-psychiatric
Psychiatric
Emergency services Non-psychiatric
Psychiatric
Non-psychiatric
Age group
Gender
2007
2008
2007
2008
2007
2008
2007
2008
2007
2008
2007
2008
15–19
Male Female Male Female Male Female Male Female Male Female Male Female Male Female Male Female Male Female Male Female Male Female
137,438 116,366 236,771 231,623 339,844 409,685 422,722 500,507 523,237 645,265 625,817 788,887 624,896 854,469 584,271 897,848 495,593 830,086 335,752 577,263 376,405 644,400
143,430 117,277 219,102 215,318 339,313 414,063 432,094 526,427 518,463 657,976 630,775 807,087 656,607 899,154 604,512 937,114 544,332 905,128 352,198 618,318 386,594 664,065
8,334,930 9,188,794 8,467,818 12,497,788 9,596,686 16,793,772 9,761,929 16,838,844 11,360,606 16,651,445 13,963,263 18,492,852 15,814,573 20,824,116 17,270,988 22,645,429 16,733,384 21,342,288 12,649,503 16,108,841 14,856,206 18,969,580
8,242,189 9,107,905 8,117,201 12,013,117 9,781,347 17,047,113 10,180,499 17,520,935 11,511,531 16,825,267 14,011,708 18,488,383 16,588,179 21,688,509 18,061,934 23,549,052 18,416,057 23,315,174 13,566,603 17,080,855 15,502,252 19,717,134
5,257 3,060 12,999 6,468 18,203 11,843 25,155 14,599 27,674 17,471 28,726 17,885 23,533 17,895 17,367 15,080 10,948 10,340 6,088 6,207 4,921 5,425
5,005 3,218 12,188 6500 18,193 12,072 25,967 15,410 30,005 19,092 32,802 19,993 28,900 20,246 20,831 17,235 13,289 12,361 7,139 6,731 5,251 5,404
71,858 51,534 94,970 110,104 111,540 243,586 132,050 265,523 176,566 182,848 239,649 176,562 292,803 220,100 344,845 258,371 358,841 274,463 301,148 239,378 379,009 323,804
69,788 50,988 89,498 102,924 110,680 236,936 140,292 275,667 181,748 191,798 248,688 184,160 314,040 233,692 366,674 272,559 399,617 298,291 321,327 249,515 394,849 332,531
2,350 3,300 5,836 6,686 8,667 9,757 10,470 10,849 12,150 12,749 12,318 12,346 10,484 11,158 7,868 9,730 5,496 7,340 3,042 4,256 2,973 4,051
2,406 3,121 4,957 5,816 8,132 9,245 10,723 10,461 10,938 11,935 12,302 12,335 10,397 10,786 8,317 9,463 5,601 7,477 3,085 4,518 2,963 4,108
313,982 249,730 362,150 352,329 332,580 367,676 289,305 292,978 288,100 250,331 304,424 251,578 309,990 278,045 307,744 294,879 272,801 266,295 198,203 196,608 233,858 236,189
303,045 239,352 334,290 326,656 324,600 360,853 288,446 297,277 278,785 245,633 296,292 245,838 310,264 278,325 310,329 295,538 291,345 282,773 202,149 202,891 233,712 236,902
20–24 25–29 30–34 35–39 40–44 45–49 50–54 55–59 60–64 65–69
utilization, the frequency of service usage was presented in two ways: (1) by persons; (2) by times. To determine the correlates of health service utilization, we used univariate logistic and linear regression analyses to identify the correlates of emergency and inpatient service use. Then, multivariate regression analyses were employed to examine the influence of these correlates on service utilization. This study used SAS program v9.2 (SAS Institute Inc, Cary NC, USA) for statistical analysis. The significant level was p b 0.05. 3. Results 3.1. Demographics and statistics The cohort included 789 heroin users with the mean age of 34.7 ± 7.8 years. Among them, 87.0% were male, 22.4% were HIV carriers, and 90.7% were HCV carriers. The distribution of the highest level of education was 55.9% for junior high school, followed by 30.9% for senior vocational or high school and 12.6% for primary school. The average duration
Table 2 Demographic data of the heroin abusers. Mean ± SD or N (%) Mean age (years) Male Onset of heroin abuse (years) HIV carriers Educational levels Primary school Junior high school Senior vocational/high school College or university Unemployed Marital status Married Single Unmarried partner Divorced
34.7 ± 7.8 686 (87.0%) 28.9 ± 8.1 177 (22.4%) 99 (12.6%) 441 (55.9%) 244 (30.9%) 5 (0.6%) 419 (53.1%) 213 (27.0%) 381 (48.3%) 28 (3.6%) 167 (21.2%)
of heroin use was 6.7 ± 5.2 years, and the mean age of onset was 28.9 ± 8.1 years. Regarding marital status, 48.3% were single and 21.2% were divorced. More than half (53.1%) were unemployed (Table 2). 3.2. Utilization of emergency service Among the 789 heroin users, 154 (19.5%) had visited the ED. According to medical records, 112 patients (14.2%) had asked for medical help, 62 patients (7.9%) had come for surgical complaints, 16 (2.0%) had received psychiatric evaluation, and 2 (0.3%) had gynecologic and obstetric problems. These amounted to a total of 298 ED visits during the 2year observation period. There were 11 patients (1.4%) whose ED visits exceeded 5 times in 2 years. 3.3. Utilization of inpatient service Of the total patients, 92 (11.7%) had been hospitalized 138 times (Supplemental Table 1). These subjects were most frequently admitted to the infectious disease department (n = 33, 4.2%) due to AIDS (n = 23), cellulitis (n = 4), pneumonia (n = 2), infectious arthritis (n = 1), or vertebrae infection (n = 1). The second most common admission was to the orthopedic department (n = 18, 2.3%), and third was to the gastroenterology department (n = 11, 1.4%) admissions. Seven patients (0.9%) had been admitted to the psychiatric unit. In the 2-year period, 8 patients were hospitalized 3 times or more. Of the 33 patients who had been admitted to the infectious disease department, 24 had only one admission, and 6 were admitted twice. The remaining 3 patients had been admitted 3, 5, and 8 times, respectively. 3.4. Utilization of outpatient service The data on clinical visits showed a pattern similar to that found in inpatient treatment. The 789 subjects made a clinical visit on 1945 occasions during the 2-year period (Supplemental Table 2). Outpatient visits due to infectious diseases occurred with the highest frequency (308 patient-visits by 68 patients), followed by gastroenterological (101 patient-visits by 58 patients) and orthopedic problems (85 patient-visits by 65 patients). Each of those with infectious disease
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received clinical follow-up an average 4.5 times. However, each patient with gastrointestinal disease sought outpatient treatment in the gastroenterology department an average of 1.7 times, and those with orthopedic problems were seen in the orthopedic clinic an average of 1.3 times. 3.5. Main diagnoses on discharge Of the 138 admissions, the most common diagnostic category was soft tissue or skin infection, accounting for 21 admissions. The next 2 most common diagnostic categories were traumatic fracture and osteomyelitis or diskitis, each accounting for 16 admissions. The fourth most common diagnosis was pneumonia. Some severe medical conditions such as gastrointestinal bleeding, infectious endocarditis, and cardiovascular and cerebrovascular diseases occurred with relatively lower frequencies (Supplemental Table 3). 3.6. Comparison to the nationwide database Heroin users had approximately 1.1-fold ED visits, 0.8-fold hospitalization, and 0.1-fold outpatient visits in non-psychiatric and overall health services compared to the predicted values based on national statistics in 2007 and 2008 standardized by sex and age distribution. In terms of psychiatric service for heroin users, there was a 36% increase of emergency visit and a 44% reduction of hospitalization than the national statistics, yet with a 167% increase of outpatient visit (Table 3). 3.7. Factors related to health service utilization Using either univariate or multivariate logistic regression, educational level was significantly associated with ED visits and hospitalization (Table 4). Meanwhile, HIV status was a significant factor for hospitalization, but not for ED visits. The results were similar using linear regression, in that HIV status was still significantly associated with the frequency of hospitalization. Educational level was also associated with the frequency of ED visits and hospitalizations; however, the effect on the frequency of ED visits was no longer there (p = 0.061) when other factors were controlled. Of note, HIV carriers were less often admitted but were associated with a higher frequency of admissions. The rates of hospitalization stratified by educational level were 20.2%, 12.2%, 6.6%, and 40.0% in the order of primary school, junior high school, senior vocational or high school, and college or university. The frequencies of hospitalization were 0.39 ± 1.17 (mean ± SD), 0.16 ± 0.49, 0.10 ± 0.44, and 0.40 ± 0.55 times, respectively, from the low to the high educational level group.
Table 3 Two years of health service utilization per person in the cohort of heroin users (n = 789) and the predicted values estimated by the nationwide annual statistics for 2007–2008 standardized by sex and age distribution. Heroin users
Predicted values
Ratio (observed/predicted)
All health services Emergency Hospitalization Outpatient visits
0.378 0.175 2.465
0.340 0.230 14.018
1.11 0.76 0.18
Psychiatric Emergency Hospitalization Outpatient visits
0.015 0.014 1.385
0.011 0.025 0.519
1.36 0.56 2.67
Non-psychiatric Emergency Hospitalization Outpatient visits
0.362 0.161 1.080
0.329 0.205 13.499
1.10 0.79 0.08
4. Discussion To our knowledge, this is the first study to present the health service utilization of heroin abusers in an Asian population. Our study showed that heroin abusers had more ED visits but fewer hospitalizations and outpatient visits than the general public during a 2-year observation period; this held true for non-psychiatric health services and all health services, as well. In terms of psychiatric service utilization, heroin abusers still had higher ED visits and less hospitalization compared to national statistics, yet they had more outpatient visits per person than predicted. We also found that the infectious disease department, gastroenterology department, and orthopedic department were the three departments most frequently visited or the most frequent sources of hospitalization. Most inpatient services were related to infection of various kinds. As for the factors that determined the more expensive health service utilization, i.e., ED and hospitalization, educational levels were associated with utilization or not, and with frequency of utilization. HIV infection was associated with increased hospitalizations but not related to the frequency of ED visits. Consistent with previous findings in Western countries (Laine et al., 2001; McGeary & French, 2001; Selwyn et al., 1993), we found that heroin abusers utilized more emergency services but fewer inpatient care both in psychiatric and non-psychiatric health services compared to national statistics. In contrast, a salient reduction of outpatient service utilization of non-psychiatric conditions was found, suggesting that regular medical care in outpatient or inpatient settings may be hindered and resulted in relatively frequent use of high-expense emergency care. Although there was a 167% increase of psychiatric outpatient visits among heroin abusers than the predicted value of national statistics, we believe that there existed an unmatched need because the psychiatric comorbidities of heroin abusers were expected to be much higher than in the general population (Brooner, King, Kidorf, Schmidt, & Bigelow, 1997; Conway, Compton, Stinson, & Grant, 2006; Kessler et al., 1996; Strain, 2002). This notion is supported by the extremely low frequency of psychiatric hospitalizations (0.56 times), yet greater frequency of emergency service utilization (1.36 times). Another fact, since the study hospital is the only general hospital to provide psychiatric inpatient and emergency services in Douliou City and the major hospital in Yunlin County during the study period, the utilization of psychiatric services is hard to underestimate. We also observed that heroin abusers might tend to ignore their physical problems and refuse referral. Their habitual way to cope with anxiety, depression or insomnia is to use heroin, if they can afford it. Similar to Western studies, the frequency of inpatient and outpatient service utilization in our study was mostly due to infectious diseases, orthopedic problems, and gastroenterological disorders, showing that the main health problems of heroin addicts were related to blood-born viral or bacterial infection (Michaud et al., 2001; Sadock et al., 2007; Skeie et al., 2008; Stein, 1999), skin or soft tissue infection (Centers for Disease Control and Prevention, 2001; Stein, 1999), and accidental injury (Evans et al., 2012; Skeie et al., 2008). It has been suggested that local infection was directly related to needle injection, whereas diskitis usually originated from hematogenous spread of systemic infection. Our findings that heroin users were more frequently admitted for cellulitis, bone infections, and peptic ulcer disease reflects the fact that many drug abusers did not receive proper treatment for infection in time. On the other hand, a high prevalence of accidental traumatic injury may likely be associated with violent victimization (Darke, Torok, Kaye, Ross, & McKetin, 2010). It is interesting to find that the infectious disease department not only had the highest outpatient numbers, but also the highest followup frequency. One explanation is that the case management strategy with integrated services for HIV-positive patients probably strengthened adherence, thus reducing the drop-out rate and lowering the barrier for delivery of HIV-related care. Likewise, Sambamoorthi et al. found that intravenous drug users with AIDS who participated in
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Table 4 Univariate and multivariate analyses of correlates of emergency and inpatient service utilization by logistic and linear regression model. Emergency
Hospitalization
Visitors v. none
Frequency of utilization
OR
95%CI
Estimate
SE
t value
OR
Visitors v. none 95%CI
Estimate
Frequency of utilization SE
t value
Univariate analysis Male Age HIV Married Education Employed Year of heroin use
1.094 0.994 0.873 1.303 1.436* 1.191 1.012
0.642–1.863 0.971–1.017 0.570–1.336 0.844–2.012 1.080–1.910 0.824–1.723 0.965–1.039
0.000 0.005 −0.049 −0.022 −0.111* −0.053 −0.002
0.105 0.005 0.084 0.080 0.054 0.071 0.007
0.00 1.12 −0.59 −0.28 −2.04 −0.74 −0.29
1.641 1.008 0.333*** 1.100 1.626** 1.201 1.013
0.906–2.972 0.978–1.038 0.208–0.533 0.652–1.858 1.142–2.315 0.761–1.896 0.967–1.062
−0.032 0.002 0.238*** −0.021 −0.107* −0.059 −0.005
0.068 0.003 0.054 0.052 0.035 0.046 0.005
−0.46 0.78 4.42 −0.40 −3.04 −1.28 −1.06
Multivariate analysis Male Age HIV Married Education Employed Year of heroin use
1.090 0.997 0.970 1.377 1.440* 1.114 1.008
0.628–1.894 0.971–1.023 0.625–1.506 0.879–2.156 1.062–1.953 0.760–1.633 0.969–1.048
−0.003 0.004 −0.076 −0.051 −0.109 −0.046 −0.005
0.108 0.005 0.086 0.082 0.058 0.073 0.008
−0.02 0.77 −0.88 −0.62 −1.88 −0.63 −0.68
1.576 1.006 0.368*** 1.088 1.547** 0.94 1.016
0.839–2.959 0.974–1.039 0.226–0.600 0.627–1.890 1.048–2.285 0.581–1.522 0.966–1.069
−0.023 0.004 0.222*** −0.032 −0.081* −0.020 −0.008
0.069 0.003 0.055 0.053 0.037 0.047 0.005
−0.34 1.09 4.02 −0.60 −2.19 −0.42 −1.64
*p b 0.05, **p b 0.01, ***p b 0.001.
MMT had better adherence to antiretrovirals (Sambamoorthi, Warner, Crystal, & Walkup, 2000). Second, the treatment course for AIDS, skin infections, and osteomyelitis at the infectious disease department is usually longer than for other problems such as fracture or common gastroenterological complaints like dyspepsia. Third, it is also possible that despite national health insurance coverage of most expenses of medical treatment, the full subsidization of HIV patients in MMT might indirectly enhance medical adherence by keeping patients in the integrated MMT program. Our finding that educational level was significantly associated with both ED visits and hospitalization has not been reported in previous studies of heroin abusers. The subsequent analysis showed that heroin users with a college degree and those with a primary school degree were admitted more than the majority group with a high school degree. We hypothesized that the less-educated addicts had more medical morbidities while the college-degree addicts were more knowledgeable and were more willing to seek medical care. This notion can be supported by the existing trend of the lower educated groups having a higher prevalence of HIV positive (34.3%, 24.5%, 14.3%, 0%, chi-square test p = 0.0002). Even so, educational level remains a significant factor in the multivariate analysis when adjusting HIV status and other factors. However, the number of college-degree addicts was extremely low in this cohort (n = 5) and the results should be interpreted cautiously. Another fact which should be considered is the lower educational attainment of our cohort compared to previous studies. The proportion of those with an educational attainment below 9 years (68.5%) was much higher than in a survey of literate methadone patients (29%) and a study of injection drug abusers in a prison (45.6%) in urbanized northern Taiwan (Chu et al., 2009; Lee et al., 2011; Ministry of Education, Taiwan, 2012), but closer to the regional statistics in Yunlin (47.9% in 2007) (Household Registration Services of Yunlin County, Taiwan, 2012). It is possible that our study population may be more representative of injection heroin abusers in central Taiwan, whose average educational attainment is lower. Yet, the young age at first use of heroin and the predominance of middle-aged males were similar to prior studies (Chu et al., 2009; Lee et al., 2011). Our findings of HIV status being a significant factor for hospitalizationthat the carriers were less often admitted, but were significantly associated with the numbers of hospitalizations could be attributed to the case management system for HIV carriers. The case managers provide psycho-education and take responsibility to ensure adherence to outpatient services in the infectious disease department;
therefore, most serious conditions can be managed without delay so patients are less likely to visit the ED or be hospitalized. However, if immune deficiency progresses, incidence of opportunistic infection may escalate rapidly, which requires extensive inpatient treatment. Unlike some previous studies, the employment status of our subjects was not associated with medical utilization (Ponitz, Olson, Jason, Davis, & Ferrari, 2006). Additionally, females under methadone treatment did not have higher rates of hospitalization as a previous study on HIV-infected African-Americans (Boyd et al., 2004), and were not associated with a higher frequency of ED utilization (O'Toole et al., 2007). Instead of simply relying on self-reported data, the major strength of this study is the detailed review of medical records in the largest regional hospital with a MMT program in central Taiwan. However, the study results should be cautiously interpreted due to some limitations. First, the database in a medical center may not completely reflect the actual help-seeking behaviors, particularly for minor medical problems such as flu. Nevertheless, this study was primarily concerned with more severe physical diseases that are usually managed in a medical center. Second, this study focused on service-seeking behaviors of heroin addicts upon the enrollment of MMT program, and the influence of MMT on health service utilization was not assessed. How the MMT program changes service-seeking behaviors waits to be investigated further in the follow-up studies. Finally, the lower education level of our sample may limit the generalizability of our findings. In conclusion, our study demonstrated that heroin users received fewer outpatient or inpatient services, but utilized costly emergency service more than the general population. Health service utilization was mostly due to infectious diseases, orthopedic problems, and gastroenterological disorders, with the main reasons being infectious disease and accidental injury, and the major correlates being HIV status and educational levels. Although the case management system with integrated outpatient services may successfully enhance health services access and adherence, our findings suggest the necessity of psychoeducation on health management and safety behaviors (e.g., safe driving) in this population, particularly in less-educated abusers, through the MMT program as a knowledge delivery platform. Role of Funding Sources The work was supported by National Taiwan University Hospital Yunlin Branch, Taiwan (NTUHYL 98.N008). The Funding sources had no role in the preparation of the manuscript, nor did they have a role in the decision to submit the manuscript. The content of the manuscript reflects the contributions and thoughts of the authors and does not necessarily reflect the views of the funding agencies.
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Contributors Author Chien YL designed the study, wrote the proposal, analyzed the data, and prepared the manuscript. Author Chen IM searched the references, consulted the statistician, and wrote the manuscript. Author Huang CL wrote the proposal and ran the study to collect the data. Author Yeh BT assisted in clinical assessment. Conflict of Interest The authors report no conflicts of interest in relation to this paper. Acknowledgments We would like to thank Mr. Lee CW who assisted in the data preparation and the National Translational Medicine and Clinical Trial Resource Center for the suggestions on data analysis.
Appendix A. Supplementary data Supplementary data to this article can be found online at http://dx. doi.org/10.1016/j.addbeh.2015.01.042. References Boyd, S.J., Thomas-Gosain, N.F., Umbricht, A., Tucker, M.J., Leslie, J.M., Chaisson, R.E., et al. (2004). Gender differences in indices of opioid dependency and medical comorbidity in a population of hospitalized HIV-infected African-Americans. American Journal on Addictions, 13, 281–291. Brooner, R.K., King, V.L., Kidorf, M., Schmidt, C.W., Jr., & Bigelow, G.E. (1997). Psychiatric and substance use comorbidity among treatment-seeking opioid abusers. Archives of General Psychiatry, 54, 71–80. Centers for Disease Control and Prevention (2001). Soft tissue infections among injection drug users—San Francisco, California, 1996–2000. MMWR. Morbidity and Mortality Weekly Report, 50, 381–384. Centers for Disease Control R.O.C., Taiwan (2005). AIDS harm reduction plan of illicit drug users. http://www2.cdc.gov.tw/public/Attachment/822614363671.doc (accessed on 2012 August 2). Chu, F.Y., Chiang, S.C., Su, F.H., Chang, Y.Y., & Cheng, S.H. (2009). Prevalence of human immunodeficiency virus and its association with hepatitis B, C, and D virus infections among incarcerated male substance abusers in Taiwan. Journal of Medical Virology, 81, 973–978. Conway, K.P., Compton, W., Stinson, F.S., & Grant, B.F. (2006). Lifetime comorbidity of DSM-IV mood and anxiety disorders and specific drug use disorders: Results from the National Epidemiologic Survey on Alcohol and Related Conditions. Journal of Clinical Psychiatry, 67, 247–257. Darke, S., Kaye, S., & Duflou, J. (2006). Systemic disease among cases of fatal opioid toxicity. Addiction, 101, 1299–1305. Darke, S., Torok, M., Kaye, S., Ross, J., & McKetin, R. (2010). Comparative rates of violent crime among regular methamphetamine and opioid users: Offending and victimization. Addiction, 105, 916–919. D'Aunno, T., & Vaughn, T.E. (1995). An organizational analysis of service patterns in outpatient drug abuse treatment units. Journal of Substance Abuse, 7, 27–42. Evans, J.L., Tsui, J.I., Hahn, J.A., Davidson, P.J., Lum, P.J., & Page, K. (2012). Mortality among young injection drug users in San Francisco: A 10-year follow-up of the UFO study. American Journal of Epidemiology, 175, 302–308. Food and Drug Administration, Taiwan (2014). http://www.fda.gov.tw/upload/133/ 2013070314002388516.pdf (accessed on November 26 2014) Garfein, R.S., Vlahov, D., Galai, N., Doherty, M.C., & Nelson, K.E. (1996). Viral infections in short-term injection drug users: The prevalence of the hepatitis C, hepatitis B, human immunodeficiency, and human T-lymphotropic viruses. American Journal of Public Health, 86, 655–661.
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Contents lists available at ScienceDirect
Addictive Behaviors
Health service utilization of heroin abusers: A retrospective cohort study I-Ming Chen a,b, Charles Lung-Cheng Huang c,d, Bao-Juan Yeh e, Yi-Ling Chien a,f,⁎ a
Department of Psychiatry, National Taiwan University Hospital, Taiwan Institute of Health Policy and Management, College of Public Health, National Taiwan University, Taiwan c Department of Psychiatry, Chi Mei Medical Center, Taiwan d Department of Social Worker, Chia Nan University of Pharmacy and Science, Taiwan e Department of Psychiatry, National Taiwan University Hospital Yun-Lin Branch, Taiwan f Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taiwan b
H I G H L I G H T S • Heroin abusers utilized more emergency services but fewer hospital admissions. • The service utilized was mostly for blood-borne/local infection and traumatic injury. • The major correlates of service utilization were HIV status and education levels.
a r t i c l e
i n f o
Available online 12 February 2015 Keywords: Heroin abuse Medical utilization Somatic diseases Viral hepatitis Human immunodeficiency virus
a b s t r a c t Aims: This study aimed to determine the patterns of medical service utilization among heroin users and to identify the factors associated with the frequency of utilization. Methods: We conducted a retrospective/prospective cohort study of 789 heroin-using adults in a catchment area, collecting data on their usage of medical care, including inpatient care, emergency visits, and outpatient care, in a 2-year observation period. We interviewed and reviewed the medical records of 789 heroin users in a methadone clinic of a general hospital in a rural area of Taiwan. The demographic data, records of service use, diagnoses, and information on viral infection status from Jan. 1, 2007 to Dec. 31, 2008 were collected. Most patients were middle-aged and unemployed, had a basic educational level, and began their first heroin use in their twenties. Results: The health service utilization of heroin users was mostly for infectious diseases, orthopedic conditions, and gastroenterological disorders mainly due to blood-borne or local infections and traumatic injury. Heroin users utilize fewer outpatient or inpatient services, but more emergency care than the general public. The major correlates of inpatient and emergency service utilization were HIV status and education level. Conclusions: Our findings suggest that integrated outpatient services may help to enhance medical service accessibility and adherence, and also imply the necessity of putting more effort into promoting health management and safe behaviors in heroin users, particularly the lower-educated addicts. © 2015 Elsevier Ltd. All rights reserved.
1. Introduction Opioid dependence is a chronic relapsing disorder characterized by high morbidity and premature mortality (Darke, Kaye, & Duflou, 2006; Hser, Hoffman, Grella, & Anglin, 2001), especially when the opioids are abused intravenously. Needle sharing and their sexual practices Abbreviations: AIDS, acquired immunodeficiency syndrome; HBV, hepatitis B virus; HCV, hepatitis C virus; HIV, human immunodeficiency virus; MMT, methadone maintenance therapy ⁎ Corresponding author at: Department of Psychiatry, National Taiwan University Hospital, No.7 Chung San South Road, Taipei, Taiwan. Tel.: +886 2 23123456x66013; fax: +886 2 23825646. E-mail address: [email protected] (Y.-L. Chien).
http://dx.doi.org/10.1016/j.addbeh.2015.01.042 0306-4603/© 2015 Elsevier Ltd. All rights reserved.
place heroin users at high risk of human immunodeficiency virus (HIV) infection, viral hepatitis, and other infectious diseases (Garfein, Vlahov, Galai, Doherty, & Nelson, 1996), as well as a range of medical morbidities (Michaud, Murray, & Bloom, 2001; Sadock, Kaplan, & Sadock, 2007). Despite the high prevalence of comorbidities and an apparent need of medical services, patients with identified drug abuse problems do not receive adequate medical care (D'Aunno & Vaughn, 1995; Saitz, Mulvey, & Samet, 1997), and often delay treatment until their medical problems worsen, which further increases the cost of care (Gelberg, Gallagher, Andersen, & Koegel, 1997; McCoy, Metsch, Chitwood, & Miles, 2001). Nearly half of heroin users presenting at a public hospital needed care for bacterial infections, and 22% for HIV/hepatitis, with the
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majority (72%) requiring admission (Masson et al., 2002). It has also been reported that injection drug users have extremely high rates of emergency department visits (Laine et al., 2001; McGeary & French, 2001; Selwyn, Budner, Wasserman, & Arno, 1993). Evidence from another study also revealed that the social consequences of substance abuse included an increase in medical expenditures for emergency department care and hospitalizations (McGeary & French, 2001). The health service utilization of heroin abusers has been surveyed in Western countries. A comprehensive review by Stein pointed out that injection drug users are at risk of coexisting morbidities including overdoses, soft tissue infections, endocarditis, pulmonary diseases, hepatitis, and sexually transmitted diseases (Stein, 1999). Skeie et al. showed that the most common disease events were injuries, acute local infections, non-fatal overdoses, and infections during methadone maintenance therapy (MMT) (Skeie, Brekke, Lindbaek, & Waal, 2008). In Taiwan, heroin has become one of the most widely used psychoactive substances. Of the 1582 drug abuse events reported by nationwide mental health services in April 2012, 69.5% involved heroin (Food and Drug Administration, Taiwan, 2014). Relevant health problems, such as infection, have been investigated in only a few studies. For example, the seroprevalence rates of HIV antibodies, hepatitis C virus (HCV) antibodies, and hepatitis B virus (HBV) surface antigens among Taiwanese injection heroin users were 25.5%, 89.6%, and 16.7%, respectively (Chu, Chiang, Su, Chang, & Cheng, 2009). In response to the HIV epidemic, the government of Taiwan implemented a comprehensive harm reduction program targeting intravenous drug users in 2005 (Centers for Disease Control R.O.C., Taiwan, 2005), including MMT, needle and syringe exchange, health education and free antiretroviral treatment for HIV infection. The Yunlin government in central Taiwan launched a harm-reduction program in July 2006. A study examining the mortality risk among a cohort of 1616 heroin users in this program between October 2006 and December 2008 found that 26 (1.6%) people had died, with an all-cause mortality rate per 100 person years of 3.42 (Huang & Lee, 2013), suggesting a high rate of mortality. However, the pattern of morbidities and the health service utilization lack research. A systemic evaluation of the type of services needed is required. We therefore conducted a retrospective cohort study of 789 subjects who visited the MMT clinic and analyzed the health service utilization during a 2-year observation period. The objective of the present research was to elucidate the health care demands and medical care utilization of heroin abusers, that may enable us to improve health services accessibility and quality in this population. 2. Methods 2.1. Geographic information and medical system This study was implemented in a general hospital with a 1108-bed inpatient facility. The hospital is located in the political and business center of Yunlin County, an agricultural district with an area of 1290 km2 and 735,000 inhabitants. Patients can visit the hospital with full access to all medical subspecialties with or without referral. The hospital is the main provider of outpatient services, and is the only hospital to provide inpatient and emergency services in Douliou City, the administrative center of Yunlin County, in the study period. All patients who come to the hospital have national health insurance which covers most of their medical expenses. 2.2. Methadone maintenance therapy and study subjects From October 9, 2006 to December 31, 2008, a total of 789 patients participated in the MMT program at our psychiatric clinic. More than 90% of those who underwent MMT were injection heroin abusers (Huang & Lee, 2013). The DSM-IV diagnosis of opioid dependence was made by board-certificated psychiatrists via face-to-face interview.
Most of the heroin abusers (n = 520, 65.9%) voluntarily attended MMT. Among them, 343 patients (43.5%) self-paid for MMT services and 177 (22.4%) got reimbursement from the Centers for Disease of Control because of a diagnosis of HIV infection. Some patients in the latter group were referred from the acquired immunodeficiency syndrome (AIDS) clinic in the hospital, in accordance with the national health policy of the AIDS harm-reduction program. Other patients (n = 269, 34.1%) were mandatorily referred from the criminal justice system in exchange for deferred indictment for illicit drug abuse. The medical costs of MMT and anti-retroviral treatment for HIV-positive patients were totally reimbursed by the government. The HIV-negative group had to pay a part of the outpatient treatment expenses on their own, which was much less expensive than ordinary patients. 2.3. Case manager system and laboratory examinations A case manager was in charge of optimizing treatment adherence. All subjects received routine laboratory examinations including complete blood count, liver and renal function tests, HBV surface antigen, HCV and HIV antibodies on the first visit. For those who had positive results for viral hepatitis or HIV infection, the case manager would ensure further medical treatment by infectious disease or hepatology specialists. 2.4. Data collection and analysis The study was proved by the Research Ethics Committee of National Taiwan University Hospital before its implementation. All the participants completed informed consent after the study procedure was fully explained. The demographic data of the subjects were collected from interviews and medical records. To investigate the medical utilization of heroin abusers, we retrieved electronic records of inpatient, outpatient, and emergency department through the hospital administrative database from Jan. 1, 2007 to Dec. 31, 2008. The frequency of emergency visits, hospitalization, and outpatient clinic visits was counted by a research assistant and double-checked by the corresponding author. The services utilization was then categorized into psychiatric and nonpsychiatric service use for further comparisons. In an effort to clarify the reasons for admission, we retrospectively reviewed the main discharge diagnoses for each hospitalization. Afterward these discharge diagnoses were allotted to corresponding disease categories, which included infectious disease, orthopedics, gastroenterology, psychiatry, gynecology/obstetrics, cardiovascular disease, endocrinology, pulmonology, nephrology, plastic surgery, otolaryngology, cardiac and vascular surgery, neurosurgery, general medicine, general surgery, neurology, hematology, and thoracic surgery. The most frequent diagnoses as well as the most severe ones were counted. 2.5. Predicted health service utilization estimated by nationwide annual statistics To compare the health service utilization of heroin abusers to the general population of the nation, we retrieved the nationwide annual statistics of health services claimed during 2007 and 2008 (Table 1) from the public database (Ministry of Health and Welfare, Taiwan, 2013), and estimated the service utilization for each sex and age group, which was then standardized by the sex and age distribution of our cohort. 2.6. Statistical analysis A substantial portion of the cohort frequently visited the EmergencyDepartment (ED) and outpatient clinic, or had been repeatedly admitted. In the interest of studying the pattern of medical service
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Table 1 The nationwide annual statistics of health services claimed during 2007 and 2008, from age 15 to 69 years for each gender. Outpatient services Psychiatric
Inpatient services Non-psychiatric
Psychiatric
Emergency services Non-psychiatric
Psychiatric
Non-psychiatric
Age group
Gender
2007
2008
2007
2008
2007
2008
2007
2008
2007
2008
2007
2008
15–19
Male Female Male Female Male Female Male Female Male Female Male Female Male Female Male Female Male Female Male Female Male Female
137,438 116,366 236,771 231,623 339,844 409,685 422,722 500,507 523,237 645,265 625,817 788,887 624,896 854,469 584,271 897,848 495,593 830,086 335,752 577,263 376,405 644,400
143,430 117,277 219,102 215,318 339,313 414,063 432,094 526,427 518,463 657,976 630,775 807,087 656,607 899,154 604,512 937,114 544,332 905,128 352,198 618,318 386,594 664,065
8,334,930 9,188,794 8,467,818 12,497,788 9,596,686 16,793,772 9,761,929 16,838,844 11,360,606 16,651,445 13,963,263 18,492,852 15,814,573 20,824,116 17,270,988 22,645,429 16,733,384 21,342,288 12,649,503 16,108,841 14,856,206 18,969,580
8,242,189 9,107,905 8,117,201 12,013,117 9,781,347 17,047,113 10,180,499 17,520,935 11,511,531 16,825,267 14,011,708 18,488,383 16,588,179 21,688,509 18,061,934 23,549,052 18,416,057 23,315,174 13,566,603 17,080,855 15,502,252 19,717,134
5,257 3,060 12,999 6,468 18,203 11,843 25,155 14,599 27,674 17,471 28,726 17,885 23,533 17,895 17,367 15,080 10,948 10,340 6,088 6,207 4,921 5,425
5,005 3,218 12,188 6500 18,193 12,072 25,967 15,410 30,005 19,092 32,802 19,993 28,900 20,246 20,831 17,235 13,289 12,361 7,139 6,731 5,251 5,404
71,858 51,534 94,970 110,104 111,540 243,586 132,050 265,523 176,566 182,848 239,649 176,562 292,803 220,100 344,845 258,371 358,841 274,463 301,148 239,378 379,009 323,804
69,788 50,988 89,498 102,924 110,680 236,936 140,292 275,667 181,748 191,798 248,688 184,160 314,040 233,692 366,674 272,559 399,617 298,291 321,327 249,515 394,849 332,531
2,350 3,300 5,836 6,686 8,667 9,757 10,470 10,849 12,150 12,749 12,318 12,346 10,484 11,158 7,868 9,730 5,496 7,340 3,042 4,256 2,973 4,051
2,406 3,121 4,957 5,816 8,132 9,245 10,723 10,461 10,938 11,935 12,302 12,335 10,397 10,786 8,317 9,463 5,601 7,477 3,085 4,518 2,963 4,108
313,982 249,730 362,150 352,329 332,580 367,676 289,305 292,978 288,100 250,331 304,424 251,578 309,990 278,045 307,744 294,879 272,801 266,295 198,203 196,608 233,858 236,189
303,045 239,352 334,290 326,656 324,600 360,853 288,446 297,277 278,785 245,633 296,292 245,838 310,264 278,325 310,329 295,538 291,345 282,773 202,149 202,891 233,712 236,902
20–24 25–29 30–34 35–39 40–44 45–49 50–54 55–59 60–64 65–69
utilization, the frequency of service usage was presented in two ways: (1) by persons; (2) by times. To determine the correlates of health service utilization, we used univariate logistic and linear regression analyses to identify the correlates of emergency and inpatient service use. Then, multivariate regression analyses were employed to examine the influence of these correlates on service utilization. This study used SAS program v9.2 (SAS Institute Inc, Cary NC, USA) for statistical analysis. The significant level was p b 0.05. 3. Results 3.1. Demographics and statistics The cohort included 789 heroin users with the mean age of 34.7 ± 7.8 years. Among them, 87.0% were male, 22.4% were HIV carriers, and 90.7% were HCV carriers. The distribution of the highest level of education was 55.9% for junior high school, followed by 30.9% for senior vocational or high school and 12.6% for primary school. The average duration
Table 2 Demographic data of the heroin abusers. Mean ± SD or N (%) Mean age (years) Male Onset of heroin abuse (years) HIV carriers Educational levels Primary school Junior high school Senior vocational/high school College or university Unemployed Marital status Married Single Unmarried partner Divorced
34.7 ± 7.8 686 (87.0%) 28.9 ± 8.1 177 (22.4%) 99 (12.6%) 441 (55.9%) 244 (30.9%) 5 (0.6%) 419 (53.1%) 213 (27.0%) 381 (48.3%) 28 (3.6%) 167 (21.2%)
of heroin use was 6.7 ± 5.2 years, and the mean age of onset was 28.9 ± 8.1 years. Regarding marital status, 48.3% were single and 21.2% were divorced. More than half (53.1%) were unemployed (Table 2). 3.2. Utilization of emergency service Among the 789 heroin users, 154 (19.5%) had visited the ED. According to medical records, 112 patients (14.2%) had asked for medical help, 62 patients (7.9%) had come for surgical complaints, 16 (2.0%) had received psychiatric evaluation, and 2 (0.3%) had gynecologic and obstetric problems. These amounted to a total of 298 ED visits during the 2year observation period. There were 11 patients (1.4%) whose ED visits exceeded 5 times in 2 years. 3.3. Utilization of inpatient service Of the total patients, 92 (11.7%) had been hospitalized 138 times (Supplemental Table 1). These subjects were most frequently admitted to the infectious disease department (n = 33, 4.2%) due to AIDS (n = 23), cellulitis (n = 4), pneumonia (n = 2), infectious arthritis (n = 1), or vertebrae infection (n = 1). The second most common admission was to the orthopedic department (n = 18, 2.3%), and third was to the gastroenterology department (n = 11, 1.4%) admissions. Seven patients (0.9%) had been admitted to the psychiatric unit. In the 2-year period, 8 patients were hospitalized 3 times or more. Of the 33 patients who had been admitted to the infectious disease department, 24 had only one admission, and 6 were admitted twice. The remaining 3 patients had been admitted 3, 5, and 8 times, respectively. 3.4. Utilization of outpatient service The data on clinical visits showed a pattern similar to that found in inpatient treatment. The 789 subjects made a clinical visit on 1945 occasions during the 2-year period (Supplemental Table 2). Outpatient visits due to infectious diseases occurred with the highest frequency (308 patient-visits by 68 patients), followed by gastroenterological (101 patient-visits by 58 patients) and orthopedic problems (85 patient-visits by 65 patients). Each of those with infectious disease
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received clinical follow-up an average 4.5 times. However, each patient with gastrointestinal disease sought outpatient treatment in the gastroenterology department an average of 1.7 times, and those with orthopedic problems were seen in the orthopedic clinic an average of 1.3 times. 3.5. Main diagnoses on discharge Of the 138 admissions, the most common diagnostic category was soft tissue or skin infection, accounting for 21 admissions. The next 2 most common diagnostic categories were traumatic fracture and osteomyelitis or diskitis, each accounting for 16 admissions. The fourth most common diagnosis was pneumonia. Some severe medical conditions such as gastrointestinal bleeding, infectious endocarditis, and cardiovascular and cerebrovascular diseases occurred with relatively lower frequencies (Supplemental Table 3). 3.6. Comparison to the nationwide database Heroin users had approximately 1.1-fold ED visits, 0.8-fold hospitalization, and 0.1-fold outpatient visits in non-psychiatric and overall health services compared to the predicted values based on national statistics in 2007 and 2008 standardized by sex and age distribution. In terms of psychiatric service for heroin users, there was a 36% increase of emergency visit and a 44% reduction of hospitalization than the national statistics, yet with a 167% increase of outpatient visit (Table 3). 3.7. Factors related to health service utilization Using either univariate or multivariate logistic regression, educational level was significantly associated with ED visits and hospitalization (Table 4). Meanwhile, HIV status was a significant factor for hospitalization, but not for ED visits. The results were similar using linear regression, in that HIV status was still significantly associated with the frequency of hospitalization. Educational level was also associated with the frequency of ED visits and hospitalizations; however, the effect on the frequency of ED visits was no longer there (p = 0.061) when other factors were controlled. Of note, HIV carriers were less often admitted but were associated with a higher frequency of admissions. The rates of hospitalization stratified by educational level were 20.2%, 12.2%, 6.6%, and 40.0% in the order of primary school, junior high school, senior vocational or high school, and college or university. The frequencies of hospitalization were 0.39 ± 1.17 (mean ± SD), 0.16 ± 0.49, 0.10 ± 0.44, and 0.40 ± 0.55 times, respectively, from the low to the high educational level group.
Table 3 Two years of health service utilization per person in the cohort of heroin users (n = 789) and the predicted values estimated by the nationwide annual statistics for 2007–2008 standardized by sex and age distribution. Heroin users
Predicted values
Ratio (observed/predicted)
All health services Emergency Hospitalization Outpatient visits
0.378 0.175 2.465
0.340 0.230 14.018
1.11 0.76 0.18
Psychiatric Emergency Hospitalization Outpatient visits
0.015 0.014 1.385
0.011 0.025 0.519
1.36 0.56 2.67
Non-psychiatric Emergency Hospitalization Outpatient visits
0.362 0.161 1.080
0.329 0.205 13.499
1.10 0.79 0.08
4. Discussion To our knowledge, this is the first study to present the health service utilization of heroin abusers in an Asian population. Our study showed that heroin abusers had more ED visits but fewer hospitalizations and outpatient visits than the general public during a 2-year observation period; this held true for non-psychiatric health services and all health services, as well. In terms of psychiatric service utilization, heroin abusers still had higher ED visits and less hospitalization compared to national statistics, yet they had more outpatient visits per person than predicted. We also found that the infectious disease department, gastroenterology department, and orthopedic department were the three departments most frequently visited or the most frequent sources of hospitalization. Most inpatient services were related to infection of various kinds. As for the factors that determined the more expensive health service utilization, i.e., ED and hospitalization, educational levels were associated with utilization or not, and with frequency of utilization. HIV infection was associated with increased hospitalizations but not related to the frequency of ED visits. Consistent with previous findings in Western countries (Laine et al., 2001; McGeary & French, 2001; Selwyn et al., 1993), we found that heroin abusers utilized more emergency services but fewer inpatient care both in psychiatric and non-psychiatric health services compared to national statistics. In contrast, a salient reduction of outpatient service utilization of non-psychiatric conditions was found, suggesting that regular medical care in outpatient or inpatient settings may be hindered and resulted in relatively frequent use of high-expense emergency care. Although there was a 167% increase of psychiatric outpatient visits among heroin abusers than the predicted value of national statistics, we believe that there existed an unmatched need because the psychiatric comorbidities of heroin abusers were expected to be much higher than in the general population (Brooner, King, Kidorf, Schmidt, & Bigelow, 1997; Conway, Compton, Stinson, & Grant, 2006; Kessler et al., 1996; Strain, 2002). This notion is supported by the extremely low frequency of psychiatric hospitalizations (0.56 times), yet greater frequency of emergency service utilization (1.36 times). Another fact, since the study hospital is the only general hospital to provide psychiatric inpatient and emergency services in Douliou City and the major hospital in Yunlin County during the study period, the utilization of psychiatric services is hard to underestimate. We also observed that heroin abusers might tend to ignore their physical problems and refuse referral. Their habitual way to cope with anxiety, depression or insomnia is to use heroin, if they can afford it. Similar to Western studies, the frequency of inpatient and outpatient service utilization in our study was mostly due to infectious diseases, orthopedic problems, and gastroenterological disorders, showing that the main health problems of heroin addicts were related to blood-born viral or bacterial infection (Michaud et al., 2001; Sadock et al., 2007; Skeie et al., 2008; Stein, 1999), skin or soft tissue infection (Centers for Disease Control and Prevention, 2001; Stein, 1999), and accidental injury (Evans et al., 2012; Skeie et al., 2008). It has been suggested that local infection was directly related to needle injection, whereas diskitis usually originated from hematogenous spread of systemic infection. Our findings that heroin users were more frequently admitted for cellulitis, bone infections, and peptic ulcer disease reflects the fact that many drug abusers did not receive proper treatment for infection in time. On the other hand, a high prevalence of accidental traumatic injury may likely be associated with violent victimization (Darke, Torok, Kaye, Ross, & McKetin, 2010). It is interesting to find that the infectious disease department not only had the highest outpatient numbers, but also the highest followup frequency. One explanation is that the case management strategy with integrated services for HIV-positive patients probably strengthened adherence, thus reducing the drop-out rate and lowering the barrier for delivery of HIV-related care. Likewise, Sambamoorthi et al. found that intravenous drug users with AIDS who participated in
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Table 4 Univariate and multivariate analyses of correlates of emergency and inpatient service utilization by logistic and linear regression model. Emergency
Hospitalization
Visitors v. none
Frequency of utilization
OR
95%CI
Estimate
SE
t value
OR
Visitors v. none 95%CI
Estimate
Frequency of utilization SE
t value
Univariate analysis Male Age HIV Married Education Employed Year of heroin use
1.094 0.994 0.873 1.303 1.436* 1.191 1.012
0.642–1.863 0.971–1.017 0.570–1.336 0.844–2.012 1.080–1.910 0.824–1.723 0.965–1.039
0.000 0.005 −0.049 −0.022 −0.111* −0.053 −0.002
0.105 0.005 0.084 0.080 0.054 0.071 0.007
0.00 1.12 −0.59 −0.28 −2.04 −0.74 −0.29
1.641 1.008 0.333*** 1.100 1.626** 1.201 1.013
0.906–2.972 0.978–1.038 0.208–0.533 0.652–1.858 1.142–2.315 0.761–1.896 0.967–1.062
−0.032 0.002 0.238*** −0.021 −0.107* −0.059 −0.005
0.068 0.003 0.054 0.052 0.035 0.046 0.005
−0.46 0.78 4.42 −0.40 −3.04 −1.28 −1.06
Multivariate analysis Male Age HIV Married Education Employed Year of heroin use
1.090 0.997 0.970 1.377 1.440* 1.114 1.008
0.628–1.894 0.971–1.023 0.625–1.506 0.879–2.156 1.062–1.953 0.760–1.633 0.969–1.048
−0.003 0.004 −0.076 −0.051 −0.109 −0.046 −0.005
0.108 0.005 0.086 0.082 0.058 0.073 0.008
−0.02 0.77 −0.88 −0.62 −1.88 −0.63 −0.68
1.576 1.006 0.368*** 1.088 1.547** 0.94 1.016
0.839–2.959 0.974–1.039 0.226–0.600 0.627–1.890 1.048–2.285 0.581–1.522 0.966–1.069
−0.023 0.004 0.222*** −0.032 −0.081* −0.020 −0.008
0.069 0.003 0.055 0.053 0.037 0.047 0.005
−0.34 1.09 4.02 −0.60 −2.19 −0.42 −1.64
*p b 0.05, **p b 0.01, ***p b 0.001.
MMT had better adherence to antiretrovirals (Sambamoorthi, Warner, Crystal, & Walkup, 2000). Second, the treatment course for AIDS, skin infections, and osteomyelitis at the infectious disease department is usually longer than for other problems such as fracture or common gastroenterological complaints like dyspepsia. Third, it is also possible that despite national health insurance coverage of most expenses of medical treatment, the full subsidization of HIV patients in MMT might indirectly enhance medical adherence by keeping patients in the integrated MMT program. Our finding that educational level was significantly associated with both ED visits and hospitalization has not been reported in previous studies of heroin abusers. The subsequent analysis showed that heroin users with a college degree and those with a primary school degree were admitted more than the majority group with a high school degree. We hypothesized that the less-educated addicts had more medical morbidities while the college-degree addicts were more knowledgeable and were more willing to seek medical care. This notion can be supported by the existing trend of the lower educated groups having a higher prevalence of HIV positive (34.3%, 24.5%, 14.3%, 0%, chi-square test p = 0.0002). Even so, educational level remains a significant factor in the multivariate analysis when adjusting HIV status and other factors. However, the number of college-degree addicts was extremely low in this cohort (n = 5) and the results should be interpreted cautiously. Another fact which should be considered is the lower educational attainment of our cohort compared to previous studies. The proportion of those with an educational attainment below 9 years (68.5%) was much higher than in a survey of literate methadone patients (29%) and a study of injection drug abusers in a prison (45.6%) in urbanized northern Taiwan (Chu et al., 2009; Lee et al., 2011; Ministry of Education, Taiwan, 2012), but closer to the regional statistics in Yunlin (47.9% in 2007) (Household Registration Services of Yunlin County, Taiwan, 2012). It is possible that our study population may be more representative of injection heroin abusers in central Taiwan, whose average educational attainment is lower. Yet, the young age at first use of heroin and the predominance of middle-aged males were similar to prior studies (Chu et al., 2009; Lee et al., 2011). Our findings of HIV status being a significant factor for hospitalizationthat the carriers were less often admitted, but were significantly associated with the numbers of hospitalizations could be attributed to the case management system for HIV carriers. The case managers provide psycho-education and take responsibility to ensure adherence to outpatient services in the infectious disease department;
therefore, most serious conditions can be managed without delay so patients are less likely to visit the ED or be hospitalized. However, if immune deficiency progresses, incidence of opportunistic infection may escalate rapidly, which requires extensive inpatient treatment. Unlike some previous studies, the employment status of our subjects was not associated with medical utilization (Ponitz, Olson, Jason, Davis, & Ferrari, 2006). Additionally, females under methadone treatment did not have higher rates of hospitalization as a previous study on HIV-infected African-Americans (Boyd et al., 2004), and were not associated with a higher frequency of ED utilization (O'Toole et al., 2007). Instead of simply relying on self-reported data, the major strength of this study is the detailed review of medical records in the largest regional hospital with a MMT program in central Taiwan. However, the study results should be cautiously interpreted due to some limitations. First, the database in a medical center may not completely reflect the actual help-seeking behaviors, particularly for minor medical problems such as flu. Nevertheless, this study was primarily concerned with more severe physical diseases that are usually managed in a medical center. Second, this study focused on service-seeking behaviors of heroin addicts upon the enrollment of MMT program, and the influence of MMT on health service utilization was not assessed. How the MMT program changes service-seeking behaviors waits to be investigated further in the follow-up studies. Finally, the lower education level of our sample may limit the generalizability of our findings. In conclusion, our study demonstrated that heroin users received fewer outpatient or inpatient services, but utilized costly emergency service more than the general population. Health service utilization was mostly due to infectious diseases, orthopedic problems, and gastroenterological disorders, with the main reasons being infectious disease and accidental injury, and the major correlates being HIV status and educational levels. Although the case management system with integrated outpatient services may successfully enhance health services access and adherence, our findings suggest the necessity of psychoeducation on health management and safety behaviors (e.g., safe driving) in this population, particularly in less-educated abusers, through the MMT program as a knowledge delivery platform. Role of Funding Sources The work was supported by National Taiwan University Hospital Yunlin Branch, Taiwan (NTUHYL 98.N008). The Funding sources had no role in the preparation of the manuscript, nor did they have a role in the decision to submit the manuscript. The content of the manuscript reflects the contributions and thoughts of the authors and does not necessarily reflect the views of the funding agencies.
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Contributors Author Chien YL designed the study, wrote the proposal, analyzed the data, and prepared the manuscript. Author Chen IM searched the references, consulted the statistician, and wrote the manuscript. Author Huang CL wrote the proposal and ran the study to collect the data. Author Yeh BT assisted in clinical assessment. Conflict of Interest The authors report no conflicts of interest in relation to this paper. Acknowledgments We would like to thank Mr. Lee CW who assisted in the data preparation and the National Translational Medicine and Clinical Trial Resource Center for the suggestions on data analysis.
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