Effects of varenicline, nicotine or placebo on depressive symptoms in postmenopausal smokers.

Background: Varenicline carries a black box warning for neuropsychiatric adverse events.

Objective: We examined varenicline use and past history of major depressive disorder (MDD) on depressive symptoms during smoking cessation.

Method: This is a secondary analysis of two smoking cessation studies in 152 postmenopausal women who received placebo or nicotine patch, or 78 women who received varenicline with relaxation. Lifetime history of MDD (LH-MDD) was assessed at baseline and women with current MDD were excluded. Center for Epidemiologic Study Depression scale (CESD) measured depressive symptoms at baseline, 6 and 12 weeks.

Results: Baseline CESD scores were 5.3 + 4.4. Those with a LH-MDD reported higher CESD scores (p > .001). Those taking varenicline reported lower scores over all time periods compared to nicotine or placebo (p < .01). The differences between varenicline and the other treatments remained when controlling for LH-MDD, indicating an independent effect. CESD scores were associated with concurrent smoking status (p < .001), and with withdrawal symptoms (p < .001).

Conclusion: CESD score were lower in those receiving varenicline, whether this is due to an anti-depressant effect, subject selection, use of relaxation or another cause is unknown. Varenicline does not increase depressive symptoms during smoking cessation in postmenopausal women without current MDD. Subjects with a LH-MDD are susceptible to developing depressive symptoms during smoking cessation, regardless of pharmacologic aid.

Scientific Significance: Pharmacologic aids did not increase depression symptoms in this select population of postmenopausal women without current depression. Smoking cessation does increase depressive symptoms in those with LH-MDD, though the degree of increase was not clinically meaningful.