Abstract P190: Developing a Reproductive Risk Prediction Model for Coronary Heart Disease in Women: The Women’s Health Initiative Observational Study
Introduction: The 2011 AHA prevention guidelines recommend taking a pregnancy history in women for the aim of CHD risk stratification. Thus, we developed a reproductive history risk model for coronary heart disease (CHD) in women as the basis of a reproductive risk score.
Methods: Data from 68,280 women in the Women’s Health Initiative Observational Study (WHI-OS) with ≥ one pregnancy and non-missing reproductive data, were used to construct a multivariable Cox proportional hazards model for CHD (MI, CHD death, revascularization) prediction. Follow up time began at enrollment and went until CHD event, loss to follow-up, death or censoring on September 30, 2010 (mean (SD) follow up=11.2 (3.2) years). An age-adjusted model was developed including candidate reproductive factors: age at menarche, menstrual regularity, number of live births, age at first birth, # of stillbirths, # of miscarriages, # of tubal pregnancies, subfertility (trying to conceive unsuccessfully for 1 year), subfertility cause, and breastfeeding for ≥ 1 month. Model discrimination was tested with a C-statistic. A second model also included race/ethnicity, education and income.
Results: Among 68,280 women in the WHI-OS with at least one pregnancy, there were 5871 CHD events with a corresponding annualized rate of 0.67%. Mean (SD) age at baseline was 63.4 (7.3) years. The following variables were associated with CHD: enrollment age, age at menarche, menstrual irregularity, number of stillbirths, number of miscarriages, and breastfeeding for at least 1-month (Table 1, C-statistic 0.66). Addition of income, race/ethnicity and education to the multivariable model did not significantly affect results.
Conclusions: A reproductive risk model may predict CHD in post-menopausal women with modest ability to discriminate outcome. Determining if these factors can accurately predict mid-life CHD above and beyond classic CHD risk factors is an important next step.
- © 2013 by American Heart Association, Inc.