Question  Is 12 months of transdermal estradiol and intermittent micronized progesterone more effective than placebo in preventing the development of depressive symptoms in the menopause transition and early postmenopausal period?

Findings  In this randomized clinical trial that included 172 perimenopausal and early postmenopausal women, 32.3% of women receiving placebo developed clinically significant depressive symptoms, while 17.3% of women taking transdermal estradiol and intermittent micronized progesterone did so.

Meaning  If confirmed in future research, clinicians may consider prescribing hormone therapy to mitigate the increased risk of clinically significant depressive symptoms that accompany the menopause transition and early postmenopausal period.

Importance  The menopause transition and early postmenopausal period are associated with a 2- to 4-fold increased risk for clinically significant depressive symptoms. Although a few studies suggest that hormone therapy can effectively manage existing depression during this time, to our knowledge, there have been no studies testing whether hormone therapy can prevent the onset of perimenopausal and early postmenopausal depressive symptoms.

Objective  To examine the efficacy of transdermal estradiol plus intermittent micronized progesterone (TE+IMP) in preventing depressive symptom onset among initially euthymic perimenopausal and early postmenopausal women. A secondary aim was to identify baseline characteristics predicting TE+IMP’s beneficial mood effects.

Design, Setting, and Participants  Double-blind, placebo-controlled randomized trial at the University of North Carolina at Chapel Hill from October 2010 to February 2016. Participants included euthymic perimenopausal and early postmenopausal women from the community, aged 45 to 60 years.

Interventions  Transdermal estradiol (0.1 mg/d) or transdermal placebo for 12 months. Oral micronized progesterone (200 mg/d for 12 days) was also given every 3 months to women receiving active TE, and identical placebo pills were given to women receiving placebo.

Main Outcome Measures  Scores on the Center for Epidemiological Studies–Depression Scale (CES-D), assessed at baseline and months 1, 2, 4, 6, 8, 10, and 12 after randomization, and the incidence of clinically significant depressive symptoms, defined as a CES-D score of at least 16.

Results  Of 172 participants, 130 were white (76%), and 70 were African American (19%), with a mean household income of $50 000 to $79 999. The mean age was 51 years, and 43 developed clinically significant depressive symptoms. Women assigned to placebo were more likely than those assigned to TE+IMP to score at least 16 on the CES-D at least once during the intervention phase (32.3% vs 17.3%; odds ratio [OR], 2.5; 95% CI, 1.1-5.7; P = .03) and had a higher mean CES-D score across the intervention period (P = .03). Baseline reproductive stage moderated the effect of treatment (β, −1.97; SEM, 0.80; P for the interaction = .03) such that mood benefits of TE+IMP vs placebo were evident among women in the early menopause transition (β, −4.2; SEM, 1.2; P < .001) but not the late menopause transition (β, −0.9; SEM, 0.3; P = .23) or among postmenopausal women (β, −0.3; SEM, 1.1; P = .92). Stressful life events in the 6 months preceding enrollment also moderated the effect of treatment on mean CES-D score such that the mood benefits of TE+IMP increased with a greater number of events (β, 1.22; SEM, 0.40; P = .003). Baseline estradiol levels, baseline vasomotor symptoms, history of depression, and history of abuse did not moderate treatment effects.

Conclusions  Twelve months of TE+IMP were more effective than placebo in preventing the development of clinically significant depressive symptoms among initially euthymic perimenopausal and early postmenopausal women.