Abstract 14769: Reproductive Duration, Number of Live Births, and Incidence of Heart Failure in the Women's Health Initiative Study

Abstract

Introduction: Reproductive factors that are reflective of endogenous sex hormone exposure may have an impact on cardiac remodeling and the development of heart failure. We sought to identify the association between key reproductive factors, including number of live births, age at first pregnancy, and reproductive duration (age at menopause - age at menarche) with the subsequent incidence of heart failure. Methods: We studied women in the University of North Carolina heart failure adjudication cohort of the Women's Health Initiative who were systematically evaluated for the presence of heart failure hospitalization from enrollment through 2010. We employed Cox Proportional Hazards Regression analysis in age and multivariable-adjusted models to relate the number of live births, age at first pregnancy, and reproductive period to incident hospitalized heart failure. Multivariable models were adjusted for age, income, education level, ethnicity, region, body mass index, hypertension, diabetes, hyperlipidemia, breastfeeding, pregnancy loss, hysterectomy, oral contraception, and hormone replacement. Results: Among n=28,516 who completed menopause at enrollment and who had non-missing reproductive history data, there were n=1,494 cases of adjudicated heart failure with mean follow up of 13.1 years. The mean age was 63 years, mean reproductive duration was 34 years, mean age at first pregnancy was 22 years, and mean number of live births was 3. Reproductive duration was inversely associated with heart failure even after adjustment for covariates (see Table 1). Early age at first pregnancy and nulliparity were significantly associated with incident heart failure in age-adjusted models, but not in multivariable-adjusted models. Conclusions: Shorter reproductive period is associated with incident heart failure in postmenopausal women. Whether or not exposure to endogenous sex hormones underlies this relationship should be investigated in future studies.