Physical activity and risk of hot flashes among women in midlife

Objective: Hot flashes commonly affect women during menopause and are among the primary menopausal complaints for which women seek medical treatment. Recent evidence of the potential risks posed by hormone therapies has led to interest in nonhormonal interventions, including physical activity. Studies evaluating the therapeutic effects of physical activity for relief of hot flashes have been limited by small sample size, problems with hot flash classification, and assumptions regarding the timing of risk and effect. The current study evaluated the association between physical activity prior to the time of the last menstrual period (LMP) and hot flashes in a large sample maintaining an appropriate sequence of physical activity and menopausal symptoms. Methods: This study included 512 perimenopausal and postmenopausal women who participated in a population-based study of midlife health in the Baltimore metropolitan area. Questionnaires assessed self-reported physical activity levels at various ages as well as frequency and severity of hot flashes. Multiple logistic regression was used to evaluate the association between physical activity prior to LMP and each of the hot flash outcomes. Results: Highly active women between the ages of 35 and 40 were significantly more likely to report moderate to severe hot flashes (OR = 1.70, p = 0.01) and daily hot flashes (OR = 1.79, p <0.01) than minimally active women in unadjusted models. Adjustment for age and smoking status did not substantially alter these results. Conclusions: Frequent physical activity in midlife may be associated with risk of greater severity and frequency of menopausal hot flashes.