Older women who have undergone menopause are less likely than men of a similar age to die from coronary heart disease (CHD), according to a prospective cohort study of more than 30,000 residents of 10 Southern states.
Researchers Catherine Kim, MD, MPH, of the University of Michigan in Ann Arbor, and colleagues published their findings online in the Journal of the American Heart Association on July 1.
Although fewer women than men have CHD, previous research has suggested menopause is a risk factor for CHD. In this study, Kim et al analyzed data from 24,123 participants in the REGARDS (Reasons for Geographic and Racial Differences in Stroke) trial who enrolled between January 2003 and October 2007. The participants were all at least 45 years old and were from the following states that have high stroke incidence rates: Alabama, Arkansas, Georgia, Kentucky, Lousiana, Mississippi, North Carolina, South Carolina, Tennessee and Virginia.
At baseline, none of the patients had CHD. After undergoing an initial physical examination and telephone interview, they were followed every six months by a computer-assisted telephone interview and assessed for changes in cognitive function and suspected incident cardiovascular events.
Among black and white patients, women had a significantly lower rate of CHD regardless of menopause type. Women were classified as having menopause resulting from bilateral oophorectomy with or without hysterectomy; menopause resulting from hysterectomy alone; or natural menopause.
The researchers also found black women who underwent menopause had a similar risk of nonfatal CHD events compared with black men, while white women had a lower risk of nonfatal CHD events compared with white men. For white women, a younger age at menopause was associated with an increased risk of fatal CHD.
Limitations of the study included the fact that patient age at menopause was self-reported and the number of fatal CHD events was modest. Kim and colleagues also mentioned future studies should examine factors that contribute to nonfatal MI and why white women had significantly fewer CHD events than men.