During the menopausal transition, up to 85% of women experience vasomotor symptoms of hot flushes and night sweats. For many women, hot flushes may be severe; they can interfere with work and other daily activities and affect sleep quality. Hot flushes may be associated with fatigue, poor concentration, and depression. Given the recent data from the Women’s Health Initiative regarding the risks associated with long-term use of estrogen, many peri- and post-menopausal women are understandably reluctant to take menopausal hormone therapy for the treatment of hot flushes, despite its proven efficacy. Given these concerns, there is a clear need for alternative non-hormonal therapies for the treatment of hot flushes and other menopause-related symptoms.
In a recent study, Dr. Michele Evans and her colleagues at the University of California at San Francisco assessed the efficacy of the antidepressant venlafaxine (Effexor) for the treatment of postmenopausal hot flushes. In this study, 80 postmenopausal women with hot flushes (more than 14 per week) were randomized to receive either treatment with venlafaxine XR (n=40) or placebo (n=40). Venlafaxine was initiated at 37.5 mg daily for 1 week and then increased to 75 mg daily for the remainder of the study period. Subjects kept daily hot flush diaries indicating frequency and severity of their hot flushes. In addition, baseline and monthly questionnaires assessed mood, quality of life, and sexual functioning. Participants were treated for 12 weeks.
61 women completed the study (treatment,n=29; placebo,n=32). Subjects treated with venlafaxine noted a reduction in severity of hot flushes and improved quality of life as compared to those receiving placebo (p<0.001). In the venlafaxine group, there was observed a 51% reduction in hot flush scores, compared with a 15% reduction in the placebo group. Hot flush severity scores based on daily diaries were somewhat lower in the treatment group but were not statistically different than scores in the placebo group (p=0.25). Three side effects, dry mouth, sleeplessness, and decreased appetite, were significantly more frequent in the venlafaxine group. Ninety-three percent of subjects in the venlafaxine group chose to continue treatment at the conclusion of the study.
This study indicates that venlafaxine XR, 75 mg per day, is an effective treatment for postmenopausal hot flushes. Although venlafaxine resulted in a relatively modest reduction in the frequency of hot flushes and appeared to have little or no effect on the severity of hot flushes, those subjects receiving venlafaxine experienced a significant and clinically meaningful improvement in quality of life. The authors hypothesize that venlafaxine may be effective, in part, as a result of its antidepressant effects. Although it was not clear how many of the women reported clinically significant depressive symptoms at entry into the study, it is possible that improvement in mood and sense of well-being brought on by the venlafaxine may have altered the women’s perceptions of their hot flushes. When comparing the two groups at the end of the study, the two groups differed significantly in terms of their perceptions of mental health and vitality. Thus, the beneficial effects of venlafaxine may be due to mood elevation and/or an increased ability to cope with hot flushes.
Ruta Nonacs, MD PhD
Evans ML, Pritts E, Vittinghoff E, McClish K, Morgan KS, Jaffe RB. 2005. Management of postmenopausal hot flushes with venlafaxine hydrochloride: a randomized, controlled trial. Obstet Gynecol 105:161-166.