Parity and cardiovascular disease risk among older women: how do pregnancy complications mediate the association?

PURPOSE: To determine whether parity is associated with increased risk of cardiovascular disease (CVD) after accounting for perinatal complications.

METHODS: CVD prevalence, number of births, and a history of preeclampsia, term low birth weight, preterm or stillbirth were evaluated among 540 women (mean age, 80 years; 47% black) enrolled in the Pittsburgh, PA site of the Health, Aging and Body Composition Study. Biomarkers were measured and CVD status was determined by self-report and hospital records.

RESULTS: Nulliparous women (n = 89) had lower CVD prevalence compared with parous women (18.0% vs. 30.2%). Parous women without perinatal complications of interest (n = 321) had higher statin use compared with nulliparas, a trend accompanied by lower high-density lipoprotein (HDL) and higher triglycerides among women with perinatal complications (n = 130). After adjustment, parous women with no complicated births had a 1.95-fold (95% confidence interval [CI], 1.03-3.7) higher CVD prevalence compared to nulliparas. Among women with one or more pregnancy complications, CVD prevalence was 2.67 times (CI, 1.34-5.33) higher. Women with five or more births had the highest CVD prevalence (odds ratio [OR], 2.60; CI, 1.17-5.76) that was attenuated to 2.27 (1.00-5.15) after adjustment for complications of interest.

CONCLUSIONS: History of pregnancy complications and higher statin use accounted for some but not all of the excess CVD prevalence among older parous women.