title: Hospital psychiatric comorbidity and its role in heroin dependence treatment outcomes using naltrexone implant or methadone maintenance.
abstract: Our objectives were to (i) estimate lifetime prevalence of psychiatric comorbidity in heroin users and (ii) evaluate psychiatric comorbidity as a predictor of drug-related hospitalization following either (a) methadone maintenance or (b) naltrexone implant treatment. Our method consisted of retrospective, longitudinal follow-up using prospectively collected, state-wide hospital data on two cohorts of heroin-dependent persons (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition), first time treated with naltrexone implant (n = 317) or methadone (n = 521) between January 2001 and December 2002. Outcome measures were: (i) prevalence of comorbidity and (ii) changes in risk for drug-related hospitalization - categorized as 'opioid drugs', 'non-opioid drugs', and 'any drug' - to 3.5 years post-treatment. Nearly 32% had psychiatric comorbidity. In both cohorts, comorbid patients generally had significantly greater odds of drug-related hospitalization pre-treatment compared with non-comorbid counterparts. These differences generally reduced in magnitude post-treatment. Comorbid naltrexone-treated patients had less 'opioid' and 'any drug' related hospitalizations post-treatment. Similarly, comorbid methadone-treated patients had reduced hospitalization risk for 'non-opioid' and 'any drug' related hospitalization post-treatment. Treatment of persons without depression, anxiety, or personality disorder with naltrexone implant was associated with increased risk of 'non-opioid' drug-related hospitalization, while methadone treatment was associated with increased risk of 'opioid' drug-related hospitalization. Although comorbid heroin users entered treatment with significantly higher risk of drug-related hospitalization than non-comorbid users, substantial reductions in drug-related hospitalization were generally observed post-treatment. This challenges the view that comorbidity predicts poor drug treatment outcomes. Differences in research methodology were noted; recommendation for rigorous analytical methodology in future research on assessing treatment outcomes was accordingly offered.
authors.affiliation: School of Psychiatry and Clinical Neurosciences, University of Western Australia, Crawley, WA, Australia. hanh.ngo@uwa.edu.au
authors.forename: Hanh T T
authors.initials: HT
authors.lastname: Ngo
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Tait
authors.forename: Gary K
authors.initials: GK
authors.lastname: Hulse
mesh_terms: D000328:Adult; D001315:Australia / Q000453:epidemiology; D017831:Diagnosis, Dual (Psychiatry) / Q000009:adverse effects*; D004343:Drug Implants / Q000627:therapeutic use*; D005260:Female; D006556:Heroin Dependence / Q000150:complications / Q000188:drug therapy*; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D001523:Mental Disorders / Q000150:complications / Q000188:drug therapy / Q000453:epidemiology*; D008691:Methadone / Q000627:therapeutic use; D009271:Naltrexone / Q000008:administration & dosage*; D058850:Opiate Substitution Treatment / Q000523:psychology*; D015995:Prevalence
chemical_list: D004343:Drug Implants; D009271:Naltrexone; D008691:Methadone