title: Cannabis, Tobacco, Alcohol Use, and the Risk of Early Stroke: A Population-Based Cohort Study of 45 000 Swedish Men.
abstract: Current knowledge on cannabis use in relation to stroke is based almost exclusively on clinical reports. By using a population-based cohort, we aimed to find out whether there was an association between cannabis use and early-onset stroke, when accounting for the use of tobacco and alcohol.
  
  
  
  The cohort comprises 49 321 Swedish men, born between 1949 and 1951, who were conscripted into compulsory military service between the ages of 18 and 20. All men answered 2 detailed questionnaires at conscription and were subject to examinations of physical aptitude, psychological functioning, and medical status. Information on stroke events up to ≈60 years of age was obtained from national databases; this includes strokes experienced before 45 years of age.
  
  
  
  No associations between cannabis use in young adulthood and strokes experienced ≤45 years of age or beyond were found in multivariable models: cannabis use >50 times, hazard ratios=0.93 (95% confidence interval [CI], 0.34-2.57) and 0.95 (95% CI, 0.59-1.53). Although an almost doubled risk of ischemic stroke was observed in those with cannabis use >50 times, this risk was attenuated when adjusted for tobacco usage: hazards ratio=1.47 (95% CI, 0.83-2.56). Smoking ≥20 cigarettes per day was clearly associated both with strokes before 45 years of age, hazards ratio=5.04 (95% CI, 2.80-9.06), and with strokes throughout the follow-up, hazards ratio=2.15 (95% CI, 1.61-2.88).
  
  
  
  We found no evident association between cannabis use in young adulthood and stroke, including strokes before 45 years of age. Tobacco smoking, however, showed a clear, dose-response shaped association with stroke.
authors.affiliation: From the Department of Public Health Sciences (D.F., P.A., A.-K.D.) and Institute of Environmental Medicine (T.H.), Karolinska Institutet, Stockholm, Sweden; Stroke Unit, Department of Neurology, Strasbourg University Hospital, University of Strasbourg, France (V.W.); Centre for Epidemiology and Community Medicine, Stockholm County Council, Sweden (P.A.); and Centre for Social Research on Alcohol and Drugs, Stockholm University, Sweden (T.H.).
authors.forename: Daniel
authors.initials: D
authors.lastname: Falkstedt
authors.affiliation: From the Department of Public Health Sciences (D.F., P.A., A.-K.D.) and Institute of Environmental Medicine (T.H.), Karolinska Institutet, Stockholm, Sweden; Stroke Unit, Department of Neurology, Strasbourg University Hospital, University of Strasbourg, France (V.W.); Centre for Epidemiology and Community Medicine, Stockholm County Council, Sweden (P.A.); and Centre for Social Research on Alcohol and Drugs, Stockholm University, Sweden (T.H.).
authors.forename: Valerie
authors.initials: V
authors.lastname: Wolff
authors.affiliation: From the Department of Public Health Sciences (D.F., P.A., A.-K.D.) and Institute of Environmental Medicine (T.H.), Karolinska Institutet, Stockholm, Sweden; Stroke Unit, Department of Neurology, Strasbourg University Hospital, University of Strasbourg, France (V.W.); Centre for Epidemiology and Community Medicine, Stockholm County Council, Sweden (P.A.); and Centre for Social Research on Alcohol and Drugs, Stockholm University, Sweden (T.H.).
authors.forename: Peter
authors.initials: P
authors.lastname: Allebeck
authors.affiliation: From the Department of Public Health Sciences (D.F., P.A., A.-K.D.) and Institute of Environmental Medicine (T.H.), Karolinska Institutet, Stockholm, Sweden; Stroke Unit, Department of Neurology, Strasbourg University Hospital, University of Strasbourg, France (V.W.); Centre for Epidemiology and Community Medicine, Stockholm County Council, Sweden (P.A.); and Centre for Social Research on Alcohol and Drugs, Stockholm University, Sweden (T.H.).
authors.forename: Tomas
authors.initials: T
authors.lastname: Hemmingsson
authors.affiliation: From the Department of Public Health Sciences (D.F., P.A., A.-K.D.) and Institute of Environmental Medicine (T.H.), Karolinska Institutet, Stockholm, Sweden; Stroke Unit, Department of Neurology, Strasbourg University Hospital, University of Strasbourg, France (V.W.); Centre for Epidemiology and Community Medicine, Stockholm County Council, Sweden (P.A.); and Centre for Social Research on Alcohol and Drugs, Stockholm University, Sweden (T.H.). anna-karin.danielsson@ki.se.
authors.forename: Anna-Karin
authors.initials: AK
authors.lastname: Danielsson
mesh_terms: D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects / Q000453:epidemiology*; D002188:Cannabis / Q000009:adverse effects; D015331:Cohort Studies; D005500:Follow-Up Studies; D006306:Health Surveys / Q000379:methods; D006801:Humans; D008297:Male; D008385:Marijuana Smoking / Q000009:adverse effects / Q000453:epidemiology*; D008875:Middle Aged; D011159:Population Surveillance / Q000379:methods; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects / Q000453:epidemiology*; D020521:Stroke / Q000175:diagnosis / Q000453:epidemiology*; D013548:Sweden / Q000453:epidemiology; D014026:Nicotiana
keywords: adolescent; cannabis; diet; stroke