Serum brain-derived neurotrophic factor predicts responses to escitalopram in chronic posttraumatic stress disorder

Abstract

Introduction Some studies have found that antidepressants increase serum brain-derived neurotrophic factor (BDNF) levels in patients with major depression and the expression of BDNF mRNA in limbic structures of rats. Objectives This study addressed whether the SSRI escitalopram increases serum BDNF levels in subjects with PTSD and whether BDNF levels are associated with treatment response. Methods Medically healthy male subjects (N = 16) with chronic PTSD completed a 12 week open-label trial of flexible dose (5–20 mg/day) escitalopram monotherapy. BDNF levels were obtained at baseline, and at weeks 4, 8 and 12. Results PTSD symptoms significantly declined over the course of the 12 week escitalopram treatment. Despite a substantial improvement in PTSD symptoms, there was virtually no change in BDNF levels over time. Nevertheless, mean BDNF levels across the trial were strongly correlated with the slope of PTSD symptoms over the 12 weeks (r = 0.58, p = 0.018). Lower mean BDNF was associated with a greater decrease in PTSD symptoms over the course of the trial. Conclusions PTSD subjects with low BDNF levels demonstrated the largest treatment response from an agent with putative neurotrophic effects.