title: Relationships of age at menarche and menopause, and reproductive year with mortality from cardiovascular disease in Japanese postmenopausal women: the JACC study.
abstract: BACKGROUND
  Early menopause is associated with increased risk of coronary heart disease in Caucasian women. However, this association has not been examined in Asian women.
  
  
  METHODS
  We conducted a 10-year cohort study of 37,965 Japanese post-menopausal women aged 40-79 years in the Japan Collaborative Cohort (JACC) Study. Causes of death were determined based on the International Classification of Disease.
  
  
  RESULTS
  There were 487 mortality of stroke and 178 mortality of coronary heart disease. Late menarche or early menopause, or shorter duration of reproductive period was not associated with risk of mortality from coronary heart disease. However, compared with women with age at menarche < or =13 years, those with age at menarche > or =17 years tended to have increased risk of mortality from stroke: the multivariable hazard ratio was 1.32 (95% confidence interval [CI]: 0.93-1.87, p = 0.10). Compared with women with age at menopause of > or =49 years, those with age at menopause of <49 years tended to have increased risk of coronary heart disease among women aged 40-64 years; the multivariable hazard ratio was 1.85 (95% CI: 0.92-3.73, p = 0.08).
  
  
  CONCLUSIONS
  The possible association between early menopause and coronary heart disease among middle-aged women was consistent with the result of observational studies for Caucasian women, and can be explained by a protective effect of endogenous estrogen on the development of atherosclerosis.
authors.affiliation: Department of Public Health Medicine, Graduate School of Comprehensive Human Science and Institute of Community Medicine, University of Tsukuba.
authors.forename: Renzhe
authors.initials: R
authors.lastname: Cui
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Iso
authors.forename: Hideaki
authors.initials: H
authors.lastname: Toyoshima
authors.forename: Chigusa
authors.initials: C
authors.lastname: Date
authors.forename: Akio
authors.initials: A
authors.lastname: Yamamoto
authors.forename: Shogo
authors.initials: S
authors.lastname: Kikuchi
authors.forename: Takaaki
authors.initials: T
authors.lastname: Kondo
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Watanabe
authors.forename: Akio
authors.initials: A
authors.lastname: Koizumi
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Inaba
authors.forename: Akiko
authors.initials: A
authors.lastname: Tamakoshi
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D015331:Cohort Studies; D015897:Comorbidity; D003327:Coronary Disease / Q000453:epidemiology* / Q000401:mortality; D004522:Educational Status; D005260:Female; D015438:Health Behavior; D006803:Human Development; D006801:Humans; D007564:Japan; D017533:Marital Status; D008572:Menarche; D008593:Menopause; D008875:Middle Aged; D017698:Postmenopause; D020521:Stroke / Q000453:epidemiology* / Q000401:mortality