title: Body mass index and risk of stroke and myocardial infarction in a relatively lean population: meta-analysis of 16 Japanese cohorts using individual data.
abstract: BACKGROUND
  The association of overweight/obesity with the incidence of cardiovascular diseases, especially stroke, has not been comprehensively examined in relatively lean populations in which stroke is more prevalent than coronary heart disease.
  
  
  RESULTS
  Pooled individual data from 16 Japanese cohorts comprising 45 235 participants ages 40 to 89 years without previous history of cardiovascular disease were studied. During follow-up, 1113 incident strokes and 190 myocardial infarctions were identified. At baseline, mean ages of men and women were 55.4 and 56.5 years and mean body mass indices (BMI) were 23.0 and 23.4 kg/m(2), respectively. Compared with those with BMI <21.0, incidence rates of cerebral infarction in subjects with BMI ≥ 27.5 were significantly elevated in both men (hazard ratio, 1.81; 95% confidence interval [CI], 1.28 to 2.56) and women (hazard ratio, 1.65; 95% CI, 1.23 to 2.21), adjusted for age, smoking, and drinking habit. Incidence of cerebral hemorrhage was also associated positively with BMI in both men (hazard ratio, 2.51; 95% CI, 1.21 to 5.20) and women (hazard ratio, 1.98; 95% CI, 1.12 to 3.52). Adjustment for systolic blood pressure, a mediating factor, significantly attenuated most BMI association with stroke in both sexes. For myocardial infarction, the hazard ratio was 3.16 (95% CI, 1.66 to 6.01) for BMI 27.5 or greater versus less than 21.0 only in men, which appeared partly mediated by total cholesterol and SBP.
  
  
  CONCLUSIONS
  Overweight/obesity was associated with an increased risk of cerebral infarction and hemorrhage in men and women and myocardial infarction in men. Weight control may have the potential to prevent both stroke and myocardial infarction in Japan.
authors.affiliation: Department of Public Health, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya, Japan. yatsuya@gmail.com
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yatsuya
authors.forename: Hideaki
authors.initials: H
authors.lastname: Toyoshima
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Yamagishi
authors.forename: Koji
authors.initials: K
authors.lastname: Tamakoshi
authors.forename: Masataka
authors.initials: M
authors.lastname: Taguri
authors.forename: Akiko
authors.initials: A
authors.lastname: Harada
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Ohashi
authors.forename: Yoshikuni
authors.initials: Y
authors.lastname: Kita
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Naito
authors.forename: Michiko
authors.initials: M
authors.lastname: Yamada
authors.forename: Naohito
authors.initials: N
authors.lastname: Tanabe
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Iso
authors.forename: Hirotsugu
authors.initials: H
authors.lastname: Ueshima
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D002543:Cerebral Hemorrhage; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007564:Japan; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000453:epidemiology* / Q000503:physiopathology; D009765:Obesity / Q000453:epidemiology* / Q000503:physiopathology; D012306:Risk; D012737:Sex Factors; D020521:Stroke / Q000453:epidemiology* / Q000503:physiopathology; D013851:Thinness