Frequent menopausal vasomotor symptoms (VMS), including hot flashes and night sweats, lasted longer than 7 years during the transition to menopause for more than 50% of women in the Study of Women’s Health Across the Nation (SWAN). 1 Among the factors related to a longer duration of VMS:
- younger age
- African American heritage
- lower educational level
- greater perceived stress and symptom sensitivity
- higher depressive symptoms and anxiety at the first report of VMS.
Details of the study
Avis and colleagues analyzed data from SWAN, a multiracial/multiethnic study of women transitioning to menopause that was conducted from February 1996 through April 2013. The analyses included 1,449 women with frequent VMS (ie, occurring at least 6 days in the previous 2 weeks).
Baseline eligibility was age between 42 and 52 years, an intact uterus and at least one ovary, report of a menstrual cycle in the 3 months before screening, absence of pregnancy and lactation, and no use of oral contraceptives or hormone therapy (HT). Women were assessed in person at baseline and approximately annually over the course of the study (mean and maximum follow-up durations were 12.7 and 17.2 years, respectively).
The main outcomes were total VMS duration (in years) and persistence of VMS (in years) beyond the final menstrual period (FMP).
Among the findings:
- The unadjusted median total VMS duration was 7.4 years
- Women who were premenopausal or early perimenopausal when they first reported frequent VMS had the longest total duration of VMS (median, >11.8 years) and longest persistence of VMS beyond the FMP (median, 9.4 years)
- Women who were postmenopausal at the onset of VMS had the shortest total VMS duration after the FMP (median, 3.4 years; P<.001).
- The median total VMS duration varied significantly by race, with African American women reporting the longest total VMS duration (median, 10.1 years) and Japanese and Chinese women reporting the shortest total duration (median, 4.8 and 5.4 years, respectively). Non-Hispanic white women had a median total VMS duration of 6.5 years; among Hispanic women, the median was 8.9 years.
“These findings can help health-care professionals counsel patients about expectations regarding VMS and assist women in making treatment decisions based on the probability of their VMS persisting,” Avis and colleagues concluded. “In addition, the median total duration of 7.4 years highlights the limitations of guidance recommending short-term HT use and emphasizes the need to identify safe long-term therapies for the treatment of VMS.”
SWAN is the largest and longest longitudinal study to date to report on total duration of VMS and their persistence beyond the FMP.
“More than 50% of midlife women experience frequent VMS, yet clinical guidelines typically underestimate their true duration,” Avis and colleagues observed.