Self reported cannabis use as a risk factor for schizophrenia in Swedish conscripts of 1969: historical cohort study

摘要: Objectives: An association between use of cannabis in adolescence and subsequent risk schizophrenia was previously reported a follow up Swedish conscripts. Arguments were raised that this may be due to drugs other than personality traits have confounded results. We performed further analysis cohort address these uncertainties while extending the period identify additional cases. Design: Historical study. Setting: 1969-70 survey conscripts (>97% country's male population aged 18-20). Participants: 50 087 subjects: data available on self drugs, several social psychological characteristics. Main outcome measures: Admissions hospital for ICD-8/9 psychoses, as determined by record linkage. Results: Cannabis associated with an increased developing dose dependent fashion both subjects who had ever used (adjusted odds ratio linear trend increasing frequency 1.2, 95% confidence interval 1.1 1.4, P times 6.7 (2.1 21.7) only group. Similar results obtained when restricted after five years conscription, exclude prodromal cases. Conclusions: is schizophrenia, consistent causal relation. This not explained psychoactive or relating integration. #### What already known about topic What topic Use has been schizophrenia Alternative explanations include confounding such amphetamines, form medication secondary disorder #### study adds What adds Self subsequently relation This sociability traits, amphetamines drugs Self unlikely explanation observed