Cognitive-behavioral therapy, light therapy, and their combination in treating seasonal affective disorder

Abstract

Background: The need to develop supplementary or alternative treatments for seasonal affective disorder (SAD) is underscored by the significant minority (47%) of SAD patients that is refractory to light therapy, the persistence of residual symptoms despite light treatment, and poor long-term compliance with light use. Because preliminary studies suggest that cognitive and behavioral factors are involved in SAD, cognitive-behavioral therapy (CBT) warrants investigation as a possible treatment option. Methods: We piloted a 6-week randomized clinical trial to compare a standard light therapy protocol; a novel, SAD-tailored, group CBT intervention; and their combination in ameliorating and remitting a current SAD episode and as prophylaxis against episode recurrence. Depressive symptom severity and remission rates were assessed at post-treatment and at a 1-year follow-up visit to examine long-term treatment durability. Results: CBT, light therapy, and their combination all demonstrated significant reductions in depressive symptoms on two different outcome measures. Remission rates varied by measure, but did not reach statistical significance. During the subsequent winter, CBT, particularly in combination with light therapy, appeared to improve long-term outcome regarding symptom severity, remission rates, and relapse rates. No CBTtreated participant, with or without light, experienced a full SAD relapse compared to over 60% of those treated with light alone. Limitations: These results should be viewed as preliminary and are limited by the small sample size (n=23) and lack of a control group. Conclusions: The nearly half of SAD patients who do not remit with light alone may benefit from CBT as an adjunct or alternative treatment, especially as a prophylaxis against episode recurrence. Published by Elsevier B.V.

Pathogenesis and management of seasonal affective disorder

“…Of most relevance would be cognitive behavioural therapy (CBT) for which there is a large evidence base for its use in other mood disorders. Preliminar y data by Rohan et al 50,51 suggest that a tailored course of CBT is as efficacious as light therapy in the acute phase and better at preventing relapse; 52 however, there is a clear need for further study.…”

Estimating health utilities and quality adjusted life years in seasonal affective disorder research

“…Third, we used data from a pilot clinical trial (Rohan et al, 2004), which was underpowered and not designed to inform researchers about the course of SAD. The lack of significant differences among treatments using the QALY(G) scores may have reflected lack of power and not lack of treatment differences, as Rohan et al, reported significant treatment group differences at her 1-year follow-up.…”

“…The pilot data showing the efficacy of CBT for SAD can be found in Rohan et al (2004). To summarize, Rohan et al found no difference among the conditions at post-treatment, but BDI-II scores were significantly more favorable for participants in CBT and CBT + LT, when compared to LT at the one-year winter follow up.…”

“…Left untreated, SAD episodes recur annually (Sakamoto et al, 1995). Although light therapy (LT; Terman et al, 1989) and group cognitive behavioral therapy (CBT; Rohan et al, 2004) improve SAD symptoms, the outcomes used to demonstrate improvement are depression-specific. That is, measures such as the Beck Depression Inventory, 2nd Edition (BDI-II; Beck et al, 1996) can be used only to compare the effectiveness of interventions for depression.…”

“…Fig. 2 graphically displays the median estimated utilities from the pilot dataset (Rohan et al, 2004). Here, a QALY is represented as the area under the curve for a particular treatment, and in this example, is defined as the average monthly utility.…”