Hot flashes and depression are both common symptoms of the menopause transition.  Several studies have found a relationship between depression and hot flashes: depressed women are more likely to experience hot flashes and women with hot flashes are more likely to have depression.  Other studies have found no association between hot flashes and depression.

The connection between these two menopause-related symptoms has led some to hypothesize that hot flashes are causally related to the development of depression in women, suggesting that, when hot flashes and depression co-occur, hot flashes precede the onset of the mood disorder.  However, these studies have assessed hot flashes and depression concurrently, therefore it is not known whether hot flashes actually precede or follow the onset of depression.

In a recent study, Freeman and colleagues describe the temporal association between the onset of hot flashes and of depression during the menopause transition.  This is an analysis conducted in 170 women who did not have hot flashes or depression at baseline.  They are a subset of the 436 women who participated in the Penn Ovarian Aging study, a 10-year prospective cohort study of women (35 to 47 years of age) who were premenopausal or early perimenopausal at the time of study entry and who were assessed approximately once per year.

During the 10-year follow-up period, 67% of women reported hot flashes, 50% reported significant depressive symptoms (as measured by a standardized questionnaire), and 41% reported both symptoms during the study.  The strong association between hot flashes and depressive symptoms is consistent with previous findings.

When the temporal sequence between the onset of hot flashes and depressive symptoms was analyzed, the order in which the symptoms occurred varied.  Among the 70 women who experienced both hot flashes and depressive symptoms, 57% experienced depressive symptoms first (average of 2.2 years before the onset of hot flashes), 19% reported that hot flashes developed first (average of 1.5 years before onset of depressive symptoms), and 24% reported these symptoms emerged concurrently.

Other factors associated with the development of depressive symptoms before the onset of hot flashes were stress and increased body size (body mass index), whereas only changes in hormone levels were associated with the onset of hot flashes before depressive symptoms.

The results of this study indicate that hot flashes and depressive symptoms occur very frequently during the menopause transition and that they commonly occur together, although there is significant variability in the sequence in which they occur, with depressive symptoms occurring first most commonly.  This study emphasizes the heterogeneity of menopause-associated symptoms and suggests that mood disturbance during the menopause transition likely has multiple contributing factors, including some that are menopause specific (i.e., hot flashes) and others that are more related to environmental stressors.

Hadine Joffe, MD, MSc

Freeman EW, Sammel MD, Lin H. Temporal associations of hot flashes and depression in the transition to menopause. Menopause. 2009 Jul-Aug;16(4):728-34.