Menstrual and reproductive risk factors for ischemic heart disease

The role of hormones in ischemic heart disease is of considerable interest, but limited data are available pertaining to risk factors associated with endogenous hormones. We examined the association between menstrual and repr oductive factors and ischemic heart disease in a cohort of 867 white, colle ge-educated women who prospectively recorded menstrual cycle data for at le ast 5 years from their early 20s through their menopause. Ischemic heart di sease history was obtained from a self-administered (N = 714) or proxy-admi nistered (N = 153) questionnaire completed at a mean age of 73 years. The a nalysis included 44,899 person-years of follow-up and 45 cases of myocardia l infarction, angioplasty, heart bypass surgery, or ischemic heart disease- related mortality. Ischemic heart disease risk decreased with increasing ag e at menarche (age-adjusted RR 0.76 per year, 95% CI = 0.60-0.95). Consider ing menstrual cycle characteristics ages 28-32, there was little overall as sociation with length, variability, or bleeding duration. Ischemic heart di sease risk increased with later age at first birth (age adjusted RR 2.90 fo r ages 33-43 compared with 25-29) and later age at last birth (age adjusted RR 3.79 for ages greater than or equal to 40 compared with 35-39), but the re was little association with high parity.