Cardiovascular risk and the menopause
Journal of the American College of Cardiology 2006

What is the association between cardiovascular risk and the menopause? Previous research has indicated that women with an early menopause are at an increased risk of cardiovascular disease, but the results of a new study indicate that cardiovascular risk influences menopausal age, rather than vice-versa.

Researchers at centers in Utrecht, the Netherlands and Boston, USA, used data from the Framingham Heart Study, which began in 1948 and has involved long-term follow-up, performed every 2 years.

They identified from the Framingham cohort a subgroup of 695 women who were premenopausal when recruited for the study and who reached natural menopause after at least two rounds of follow-up. The researchers investigated whether premenopausal cardiovascular risk factors had any effect on age at menopause.

Risk factors and age
In their paper due to be published soon in the Journal of the American College of Cardiology, the researchers report the following associations based on their results:

• A higher premenopausal serum total cholesterol level was significantly associated with an earlier age at menopause.
• Increases in total serum cholesterol, relative weight, and blood pressure during the premenopausal period were each significantly associated with an earlier age at menopause.
• A decrease in total serum cholesterol during the premenopausal period was significantly associated with a later age at menopause.

A premenopausal decrease in blood pressure was associated with a later menopausal age, say the researchers, but this association was not statistically significant. The Framingham risk score for women at age 35 years was significantly associated with age at menopause. The researchers report that every 1 percent higher 10-year risk for coronary heart disease was associated with a mean decrease in menopausal age of 1.8 years.

They write: “Considering the risk range in this population, the effect on menopausal age could amount to more than four years in women with the highest risk.

Not mutually exclusive
Concluding, the researchers write that the results “show that levels of premenopausal risk factors for cardiovascular disease affect the age at menopause.

“This offers an alternative explanation for the seemingly adverse effect of early menopausal transition on cardiovascular disease risk.”

They note that a current view on the relationship between menopause and cardiovascular risk assumes that the reduction in estrogen levels at the menopause is a causal factor in the subsequent increase in cardiovascular risk. But, they add: “Conversely, however, menopause may not induce a change in cardiovascular risk profile, but a woman’s atherosclerotic status may influence age at onset of menopause.”

The researchers point out that the two hypotheses are not mutually exclusive.

No breast cancer risk seen with ERT
Journal of the American Medical Association 2006

Examining the risk of breast cancer in women given conjugated equine estrogen in the Women's Health Initiative study.

Long-term estrogen therapy does not appear to raise the risk of breast cancer in postmenopausal women who have had a hysterectomy, an updated analysis of data from the Women's Health Initiative (WHI) study indicates.

Although substantial epidemiologic evidence has linked the use of exogenous estrogens with an increased breast cancer incidence, preliminary analyses of the conjugated equine estrogen (CEE) alone arm of the WHI revealed fewer breast cancers in women in the CCE group, compared with controls.

Overall, the study included 10,739 women aged 50-79 years with prior hysterectomy. The women were randomly assigned to receive 0.625 mg/d of CEE or placebo for an average of 7.1 years.

In the updated analysis, Marcia Stefanick (Stanford University, California, USA) and colleagues saw nonsignificant reductions in invasive and total breast cancer (20 percent and 18 percent, respectively) in women given CEE, compared with those given placebo.

Further analysis showed that breast cancers with localized disease were 31 percent less common with CEE, while the incidence of more advanced cancers was comparable. A similar reduction was found for ductal carcinomas, the authors note.

"In conclusion, CEE alone for 7 years does not increase breast cancer incidence in postmenopausal women with hysterectomy, and may decrease the risk of early stage disease and ductal carcinomas," they conclude.