Atypical and typical winter depressive symptoms and responsiveness to light therapy, cognitive-behavioral therapy, or combination treatment /

by Johnson, Leigh G.

Title of Thesis: Atypical and Typical Winter Depressive Symptoms and Responsiveness to Light Therapy, Cognitive-Behavioral Therapy, or Combination Treatment Leigh G. Johnson, Master of Science, 2005 Thesis directed by: Kelly J. Rohan, Ph.D. Assistant Professor Department of Medical and Clinical Psychology This study examined whether atypical and typical depressive symptoms in seasonal affective disorder (SAD) differentially predict treatment outcome. Participants (N=61) fulfilled criteria for Major Depression, Recurrent with Seasonal Pattern, and completed a 6-week randomized clinical trial comparing light therapy (LT), group cognitive-behavioral therapy (CBT), or combination therapy (CBT+LT). Atypical and typical symptoms were assessed using subscales of the Structured Interview Guide for the Hamilton Rating Scale for Depression - SAD Version (SIGH-SAD). Pre-treatment atypical symptom severity correlated significantly and positively with SIGH-SAD improvement and with post-treatment response and remission status, but did not significantly predict treatment outcome in multivariate analyses. Unexpectedly, severity of hyperphagia predicted poor post-treatment response and remission. Fatigue positively predicted post-treatment response and remission. Results revealed large and comparable improvements in atypical and typical symptoms over all three treatments. These findings suggest that atypical symptom severity is associated with favorable outcomes, regardless of treatment modality. iv