Link Between Menstrual Cycle Length and Atherosclerosis During Menopause

Some 428 women enrolled in the ongoing Study of Women’s Health Across the Nation (SWAN) Daily Hormone Study (DHS) volunteered for the menopause study. Measurements included carotid intima-media thickness, brachial-ankle pulse wave velocity, menstrual cycle length, urinary hormonal patterns, and the time to final menstrual period (FMP). Other data included age, smoking status, physical activity, household/childcare activity index, sports index, “difficulty paying for basics”, diabetic status, and current medication usage. Body mass index (BMI), fasting glucose, fasting insulin, high- and low- density lipoprotein-cholesterol levels, and triglyceride levels, were collected during clinical visits.

The women experienced a total of 1808 cycles between the start of the study and their FMP. On average, participants had MTs lasting 7.36±2.51 years before their FMP. Average (SD) cycle length prior to menopause was 27.2 (5.2 days). Women in the late increase group were the youngest at menopause compared with women in the stable or early trajectory groups.

 As women in the study approached menopause, 21.8% experienced late cycle length increases at 2 years or less prior to menopause, 62% had stable trajectories with no change in cycle length, and 16.2% experienced an early increase in cycle length (as early as 5 years) prior to menopause. Women who experienced a late increase in their cycle length over the MT closer to menopause demonstrated more favorable subclinical atherosclerotic measures than those with early or stable trajectories, while women with early increases in cycle length exhibited the worst cardiometabolic risk profiles.

“Patterns of cycle length over the menopause transition (MT) seem to be a marker of future vascular health that may help identify groups at greater risk of atherosclerosis after menopause,” the researchers said, adding that higher estrogen levels after menopause have been found to be associated with greater insulin resistance, inflammatory marker levels, and a more pro-atherogenic lipid profile. “It is plausible that the late increase group is protected by not having too much estrogen at a critical time during the MT.”

Disclosure

Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.

Reference

El Khoudary SR, Qi M, Chen X, et al. Patterns of menstrual cycle length over the menopause transition are associated with subclinical atherosclerosis after menopause. Menopause. Published online October 11, 2021. doi:10.1097/GME.0000000000001876