Revisiting the duration of vasomotor symptoms of menopause: A meta-analysis

BACKGROUND: Treatment decisions about menopause are predicated on a transient duration of vasomotor symptoms. However, evidence supporting a specific duration is weak. OBJECTIVE: To estimate the natural progression of vasomotor symptoms during the menopause transition by systematically compiling available evidence using meta-analytic techniques. DATA SOURCES: We searched MEDLINE, hand searched secondary references in relevant studies, book chapters, and review papers, and contacted investigators about relevant published research. REVIEW METHODS: English language, population-based studies reporting vasomotor symptom prevalence among women in menopausal transition in time intervals based on years to or from final menstrual period were included. Two reviewers independently assessed eligibility and quality of studies and extracted data for vasomotor symptom prevalence. RESULTS: The analyses included 10 studies (2 longitudinal, 8 cross sectional) with 35,445 participants. The percentage of women experiencing symptoms increased sharply in the 2 years before final menstrual period, peaked 1 year after final menstrual period, and did not return to premenopausal levels until about 8 years after final menstrual period. Nearly 50% of all women reported vasomotor symptoms 4 years after final menstrual period, and 10% of all women reported symptoms as far as 12 years after final menstrual period. When data were examined according to symptom severity ('any' vs. 'bothersome'), bothersome symptoms peaked about 1 year earlier and declined more rapidly than symptoms of any severity level. CONCLUSIONS: Our findings suggest a median symptom duration of about 4 years among symptomatic women. A longer symptom duration may affect treatment decisions and clinical guidelines. Further prospective, longitudinal studies of menopausal symptoms should be conducted to confirm these results.