Reproductive Risk Factors and Coronary Heart Disease in the Women's Health Initiative Observational Study. - 2016

Available online from MWHC library: 1950 - present, Available in print through MWHC library: 1999 - 2006

BACKGROUND: Reproductive factors provide an early window into a woman's coronary heart disease (CHD) risk; however, their contribution to CHD risk stratification is uncertain. Copyright © 2016 American Heart Association, Inc. METHODS AND RESULTS: In the Women's Health Initiative Observational Study, we constructed Cox proportional hazards models for CHD including age, pregnancy status, number of live births, age at menarche, menstrual irregularity, age at first birth, stillbirths, miscarriages, infertility >1 year, infertility cause, and breastfeeding. We next added each candidate reproductive factor to an established CHD risk factor model. A final model was then constructed with significant reproductive factors added to established CHD risk factors. Improvement in C statistic, net reclassification index (or net reclassification index with risk categories of <5%, 5 to <10%, and >10% 10-year risk of CHD), and integrated discriminatory index were assessed. Among 72982 women (CHD events, n=4607; median follow-up,12.0 [interquartile range, 8.3-13.7] years; mean [standard deviation] age, 63.2 [7.2] years), an age-adjusted reproductive risk factor model had a C statistic of 0.675 for CHD. In a model adjusted for established CHD risk factors, younger age at first birth, number of still births, number of miscarriages, and lack of breastfeeding were positively associated with CHD. Reproductive factors modestly improved model discrimination (C statistic increased from 0.726 to 0.730; integrated discriminatory index, 0.0013; P<0.0001). Net reclassification for women with events was not improved (net reclassification index events, 0.007; P=0.18); and, for women without events, net reclassification was marginally improved (net reclassification index nonevents, 0.002; P=0.04) CONCLUSIONS: Key reproductive factors are associated with CHD independently of established CHD risk factors, very modestly improve model discrimination, and do not materially improve net reclassification.


English

0009-7322


*Coronary Artery Disease/di [Diagnosis]
*Coronary Artery Disease/ep [Epidemiology]
*Pregnancy Rate
*Reproduction
*Women's Health
Adult
Aged
Female
Humans
Longitudinal Studies
Middle Aged
Pregnancy
Pregnancy Rate/td [Trends]
Risk Factors
Young Adult


MedStar Health Research Institute


Journal Article
Observational Study
Research Support, N.I.H., Extramural
Research Support, Non-U.S. Gov't