title: Patients with nonaffective psychosis are at increased risk for heroin use disorders.
abstract: OBJECTIVE
  It is well-established knowledge that persons with nonaffective psychotic disorders often have problematic use of alcohol, cannabis and stimulants, but heroin use is usually not included. Our aim was to investigate the prevalence of heroin use disorders in patients with nonaffective psychosis.
  
  
  METHODS
  As the combination of heroin use and nonaffective psychosis is infrequent, epidemiological studies have to include large populations. The present study is a case count study using information from all psychiatric and social services in Oslo. Prevalence was calculated for four possible scenarios of minimum and maximum case counts and prevalences of nonaffective psychosis. Odds ratios were calculated for the resulting prevalences compared to the minimum and maximum prevalence of heroin use disorder in the general population.
  
  
  RESULTS
  We found between 39 and 56 subjects with nonaffective psychoses and comorbid heroin use disorder. The number of individuals with nonaffective psychosis was estimated to be between 692 and 1,730. This corresponds to a prevalence of heroin use disorder of between 2.3 and 8.1%. The odds ratio compared to the general population will range from 1.83 with a prevalence of heroin use disorder in the general population of 1.2% to 9.43 with a prevalence of 0.9%.
  
  
  CONCLUSIONS
  Individuals with nonaffective psychosis are at increased risk of heroin use.
authors.affiliation: Norwegian Centre for Addiction Research, University of Oslo, Oslo, Norway. kjersti.pedersen @ medisin.uio.no
authors.forename: Kjersti
authors.initials: K
authors.lastname: Pedersen
authors.forename: Helge
authors.initials: H
authors.lastname: Waal
authors.forename: Einar
authors.initials: E
authors.lastname: Kringlen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006556:Heroin Dependence / Q000453:epidemiology* / Q000523:psychology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D011618:Psychotic Disorders / Q000453:epidemiology* / Q000523:psychology*; D012307:Risk Factors; D055815:Young Adult