title: Risk factors for sudden cardiac death among Japanese:  the Circulatory Risk in Communities Study.
abstract: OBJECTIVE
  There is little evidence concerning risk factors for sudden cardiac death (SCD) among Asians.
  
  
  METHODS
  A prospective, nested, case-control study of Japanese patients aged between 30 and 84 years was undertaken using data collected from 26 870 participants in cardiovascular risk surveys conducted in four communities between 1975 and 2005. The incidence of SCD was ascertained by systematic surveillance, with 239 cases of SCD identified over this period. For each case of SCD, three control patients were selected, matched by age, sex, examination year, follow-up time, and community.
  
  
  RESULTS
  Hypertension, diabetes mellitus, smoking, major ST-T abnormalities, left high amplitude R waves, and increased heart rate (≥77 beat/min) were all independently associated with a 1.5-3.2-fold increase in SCD risk, whereas no associations were observed for body mass index and hypercholesterolemia. The population-attributable fraction [95% confidence interval (CI)] was 23.0% (2.9-39.0) for hypertension, 15.3% (3.8-25.5) for current smoking, 14.5% (8.0-20.5) for major ST-T abnormalities, and 8.1% (2.2-13.7) for diabetes mellitus. The number of SCD risk factors (hypertension, diabetes, smoking, and ECG abnormalities) was positively associated with increased SCD risk. The odds ratio for increased SCD risk with three or more risk factors versus zero risk factors was 5.76 (95% CI 3.20-10.39).
  
  
  CONCLUSIONS
  Among the Japanese population, hypertension, smoking, major ST-T abnormalities, left high amplitude R waves, and diabetes mellitus were associated with an increased incidence of SCD, whereas there were no associations of body mass index or hypercholesterolemia with SCD incidence.
authors.affiliation: Department of Social and Environmental Medicine, Osaka University, Suita, Japan. ohira@pbhel.med.osaka-u.ac.jp
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Ohira
authors.forename: Minako
authors.initials: M
authors.lastname: Maruyama
authors.forename: Hironori
authors.initials: H
authors.lastname: Imano
authors.forename: Akihiko
authors.initials: A
authors.lastname: Kitamura
authors.forename: Masahiko
authors.initials: M
authors.lastname: Kiyama
authors.forename: Takeo
authors.initials: T
authors.lastname: Okada
authors.forename: Kenji
authors.initials: K
authors.lastname: Maeda
authors.forename: Kazumasa
authors.initials: K
authors.lastname: Yamagishi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Noda
authors.forename: Renzhe
authors.initials: R
authors.lastname: Cui
authors.forename: Sachiko
authors.initials: S
authors.lastname: Masuda
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Kimura
authors.forename: Koji
authors.initials: K
authors.lastname: Tachikawa
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Iso
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016757:Death, Sudden, Cardiac / Q000453:epidemiology*; D005260:Female; D006801:Humans; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012307:Risk Factors