Category: Adult Depression / Dysthymia
We completed a randomized clinical trial comparing two theoretically distinct treatments for seasonal affective disorder (SAD): cognitive-behavioral therapy (CBT-SAD), which is designed to engage a cognitive vulnerability target, and light therapy (LT), which is designed to engage a chronobiological target. CBT-SAD and LT were comparably efficacious acute treatments (post-treatment remission rates = 47.6% in CBT-SAD and 47.2% in LT; Rohan et al., 2015). Here, we explore the course of individual depressive symptom offset and whether these symptoms differ in their time to remission across CBT-SAD vs. LT to inform differential mechanisms related to remission.
A sample of 177 community adults in a current episode of Major Depression, Recurrent with Seasonal Pattern were randomized to 6-weeks of CBT-SAD (n=88; twice-weekly 90-minute group sessions) or LT (n=89; 10,000-lux initiated at 30-min./day upon waking and subsequently adjusted per an algorithm). Depressive symptoms were assessed via items on the 29-item Structured Interview Guide for the Hamilton Rating Scale for Depression-SAD Version (SIGH-SAD) at pre-treatment and weekly during treatment. These secondary analyses included the 17 SIGH-SAD items endorsed by 40 or more participants at pre-treatment. Within each of the 17 included symptoms, participants with fewer than 3 weeks of missing data and who endorsed the symptom at baseline were included.
Jonah Meyerhoff– Graduate Student, University of Vermont, Burlington
Michael Young– Professor of Psychology, Illinois Institute of Technology, Chicago, Illinois
Kelly Rohan– Professor of Psychology, University of Vermont, Burlington, Vermont
Julia Camuso– Graduate Student, University of Vermont, Burlington, Vermont