A Placebo-Controlled Randomized Trial of the Effects of Escitalopram on Depressive Symptoms and Immune Function in...

This study was a randomized controlled trial investigating the effects of a selective serotonin reuptake inhibitor (SSRI) and improvement in depressive symptoms on innate immunity and inflammation in people with HIV (PWH).

The mean 17-item Hamilton Depression Rating Scale (HAMD-17) score at baseline was 19.1 for the sample (N = 108). Eligible participants were randomized to 10 weeks of double-blind therapy with either SSRI (escitalopram) or placebo. All participants concurrently received computer-assisted cognitive behavioral therapy (CCBT). Peripheral blood was obtained from each participant at baseline and at weeks 2, 4, and 10, and intracellular interferon gamma (IFN-γ) in natural killer (NK) cells, lytic units per 10⁷ NK cells (LUNKs), interleukin 6 (IL-6), and C-reactive protein (CRP) were measured.

Participants showed substantial reduction in depressive symptoms during study with final HAMD-17 score of 8.00 (average decrease of 11.0 units). However, there was no statistically significant effect of treatment, whether viewed as a group × time interaction (F _1,166 = 0.00, p = .976) or as a main effect for group (F _1,667 = 0.50, p = .479). There were no statistically significant differences between the groups on the immune parameters over time. There was little evidence that the magnitude of symptom improvement was associated with changes in immune measures.

Our study did not demonstrate superiority of treatment with SSRI+CCBT versus placebo+CCBT. Patients in both arms showed improvement of depression symptoms, which did not correlate with changes in immune markers. We found no evidence of decreased inflammation (IL-6, CRP) or immune restoration (LUNKs or intracellular IFN-γ) following treatment with CCBT with or without active escitalopram. While antidepressant treatment is indicated for PWH with depression, we observed no evidence of direct immunologic benefits.