title: Alcohol consumption at midlife and risk of stroke during 43 years of follow-up: cohort and twin analyses.
abstract: OBJECTIVE
  Although alcohol-stroke association is well known, the age-varying effect of alcohol drinking at midlife on subsequent stroke risk across older adulthood has not been examined. The effect of genetic/early-life factors is also unknown. We used cohort and twin analyses of data with 43 years of follow-up for stroke incidence to help address these gaps.
  
  
  METHODS
  All 11 644 members of the population-based Swedish Twin Registry born 1886 to 1925 with alcohol data aged ≤60 years were included. The interaction of midlife alcohol consumption by age at stroke was evaluated in Cox-regression and analyses of monozygotic twins were used. Covariates were baseline age, sex, cardiovascular diseases, diabetes mellitus, stress reactivity, depression, body mass index, smoking, and exercise.
  
  
  RESULTS
  Altogether 29% participants developed stroke. Compared with very-light drinkers (<0.5 drink/d), heavy drinkers (>2 drinks/d) had greater risk of stroke (hazard ratio, 1.34; P=0.02) and the effect for nondrinkers approached significance (hazard ratio, 1.11; P=0.08). Age increased stroke risk for nondrinkers (P=0.012) and decreased it for heavy drinkers (P=0.040). Midlife heavy drinkers were at high risk from baseline until the age of 75 years when hypertension and diabetes mellitus grew to being the more relevant risk factors. In analyses of monozygotic twin-pairs, heavy drinking shortened time to stroke by 5 years (P=0.04).
  
  
  CONCLUSIONS
  Stroke-risk associated with heavy drinking (>2 drinks/d) in midlife seems to predominate over well-known risk factors, hypertension and diabetes, until the age of ≈75 years and may shorten time to stroke by 5 years above and beyond covariates and genetic/early-life factors. Alcohol consumption should be considered an age-varying risk factor for stroke.
authors: From the International Clinical Research Center, Neurology Department, St. Anne's Hospital, Brno, Czech Republic (P.K., R.A., R.M.); School of Aging Studies, University of South Florida, Tampa (R.A., E.P.H.); Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic (R.M.); Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden (N.L.P.); and Department of Psychology, University of Southern California, Los Angeles (N.L.P.). kadlecovap@fnusa.cz.
authors: Pavla
authors: P
authors: Kadlecová
authors: From the International Clinical Research Center, Neurology Department, St. Anne's Hospital, Brno, Czech Republic (P.K., R.A., R.M.); School of Aging Studies, University of South Florida, Tampa (R.A., E.P.H.); Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic (R.M.); Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden (N.L.P.); and Department of Psychology, University of Southern California, Los Angeles (N.L.P.).
authors: Ross
authors: R
authors: Andel
authors: From the International Clinical Research Center, Neurology Department, St. Anne's Hospital, Brno, Czech Republic (P.K., R.A., R.M.); School of Aging Studies, University of South Florida, Tampa (R.A., E.P.H.); Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic (R.M.); Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden (N.L.P.); and Department of Psychology, University of Southern California, Los Angeles (N.L.P.).
authors: Robert
authors: R
authors: Mikulík
authors: From the International Clinical Research Center, Neurology Department, St. Anne's Hospital, Brno, Czech Republic (P.K., R.A., R.M.); School of Aging Studies, University of South Florida, Tampa (R.A., E.P.H.); Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic (R.M.); Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden (N.L.P.); and Department of Psychology, University of Southern California, Los Angeles (N.L.P.).
authors: Elizabeth P
authors: EP
authors: Handing
authors: From the International Clinical Research Center, Neurology Department, St. Anne's Hospital, Brno, Czech Republic (P.K., R.A., R.M.); School of Aging Studies, University of South Florida, Tampa (R.A., E.P.H.); Department of Neurology, St. Anne's University Hospital and Medical Faculty of Masaryk University, Brno, Czech Republic (R.M.); Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden (N.L.P.); and Department of Psychology, University of Southern California, Los Angeles (N.L.P.).
authors: Nancy L
authors: NL
authors: Pedersen
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000428:Alcohol Drinking / Q000009:adverse effects*; D015992:Body Mass Index; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D020022:Genetic Predisposition to Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D012042:Registries; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology / Q000209:etiology* / Q000235:genetics
keywords: alcohols; risk factors; stroke; twins