Introduction:
Men have greater risk of coronary heart disease (CHD) compared to women. It is unclear whether type of menopause affects this sex difference and if the impact is similar in blacks and whites. Moreover, women and their physicians may consider CHD risk when considering whether elective hysterectomy and/or bilateral salpingo-oophorectomy (BSO) are performed.
Hypotheses:
Women who undergo natural menopause, menopause due to BSO, and menopause due to hysterectomy alone have different risks of non-fatal CHD and acute CHD death compared to men.
Methods:
Participants in the Reasons for Geographic and Racial Differences in Stroke (REGARDS) cohort between 2003 and 2007 without CHD at baseline (n=23,086), with follow-up through December 2011. Cox proportional hazard models were used to calculate the hazard of incident CHD events in men vs. women by menopause type, stratified by black vs. white race. The main outcome measure was adjudicated incident CHD events, defined as nonfatal CHD (definite or probably myocardial infarction) and acute CHD death.
Results:
Over a median 6.0 years of follow-up, 892 incident CHD events occurred. Cox regression models adjusted for age, age at last menstrual period < 45 years, region, education level, income, CHD risk factors (total cholesterol, high-density lipoprotein, smoking, systolic blood pressure, diabetes, albumin to creatinine ratio, physical activity, C-reactive protein, body mass index and waist circumference), and use of anti-hypertensive medications, statins, and estrogen therapy. Associations of menopause with non-fatal events differed by race (p for interaction=0.03). Among white women, natural menopause (hazard ratio [HR] 0.45, 95% CI 0.31, 0.66) and surgical menopause (HR 0.65, 95% CI 0.42, 0.99) were associated with a reduced hazard of non-fatal events compared to white men. Among black women, natural menopause was marginally significantly associated with lower hazard of non-fatal events compared to men (HR 0.69, 95% CI 0.47, 1.03) but surgical menopause was not (HR 0.81, 95% CI 0.51, 1.29). For acute CHD death, women had lower risk than men regardless of their menopause type and race.
Conclusions and Relevance:
Sex differences in the risk of incident CHD events were larger among whites than blacks and varied by type of menopause. Women consistently had a lower risk of incident CHD death than men, but the magnitude of sex differences was greater in whites than blacks for non-fatal events regardless of menopause type. Menopause type was not associated with large differences in the hazard for CHD risk.
The impact of cardiovascular risk factors on the age-related excess risk of coronary heart disease