Longer menstrual cycles have been associated with greater risk of cardiovascular disease, supporting a contribution of abnormal ovarian function. We aimed to characterize trajectories of menstrual cycle length over the menopause transition (MT) and test whether these trajectories are associated with postmenopausal markers of subclinical atherosclerosis.
Women from the Study of Women's Health Across the Nation Daily Hormone Study were included if they had an observed date of the final menstrual period (FMP), recorded cycle lengths from ≥2 annual menstrual cycles (mean±SD: 4.22 ± 1.91 cycles), and had measurements of postmenopausal carotid intima-media thickness (cIMT) and/or brachial-ankle pulse wave velocity (baPWV). Trajectories of cycle length over the MT were identified using group-based trajectory modeling and linked with cIMT and baPWV using linear regression.
We studied 428 women who had 1,808 cycles over the MT (45.1 ± 2.3 y old at baseline visit), and of whom 263 had cIMT, and 213 had baPWV measured postmenopausally (after 13.88 ± 0.42 and 15.25 ± 0.70 y since baseline visit, respectively). Three distinct trajectories of cycle length were identified: stable (no changes in cycle length over the MT among 62.1% of women), late increase (a late increase 2 y before the FMP among 21.8%), and early-increase (an early increase 5 y before the FMP among 16.2%). Women with the late-increase pattern had significantly lower postmenopausal cIMT (0.72 mm) and baPWV (1392 cm/s) levels than the stable group (0.77 mm and 1508 cm/s, respectively) adjusting for race, concurrent age, socioeconomic status, physical activity level, and premenopausal cardiovascular risk profile.
Patterns of cycle length over the MT seem to be a marker of future vascular health that may help identify groups at greater or lesser risk of atherosclerosis after menopause.