News

For SAD Sufferers, CBT Better Than Light Therapy

In Behavior Therapy, University of Vermont psychologist Kelly Rohan, PhD, presents research on the long-term effects of different treatments for seasonal affective disorder (SAD). The first year Rohan randomized 69 people with SAD into one of four groups: light therapy treatment, cognitive behavior therapy (CBT), a combination of the two or a wait-list control. She then surveyed participants on how they were doing one year later.

Of those treated with CBT, only 7% had a recurrence compared to 36.7% of people treated with light therapy. The recurrence rate for the combination group was 5.5%. When Rohan looked at the severity of the depression that did occur, however, CBT was associated with less severe depression than those treated with either light therapy or a combination of both.

In a previous study that measured the acute affects of each treatment (immediately following six weeks of intervention), combination therapy was highly effective, with a nearly 80% remission rate compared with 50% for both CBT and light therapy alone and 20% on the wait-list.

Rohan hypothesizes that such dramatic results for the combination therapy are the result of being in a heavily monitored study with full participation. When people are left on their own to manage symptoms the subsequent winter, follow-through is much more difficult. This “watered-down” effect of a two-modality treatment, Rohan notes, has been reported for 20 years across psychology disorders of all sorts.

“People treated with only CBT—that’s all they know,” she says, “so I think they do it with gusto in the next year and reap the benefits.”

Of the light therapy group, only four people used it on their own the following winter. Rohan considers this unsurprising given the commitment the treatment requires: 30 minutes sitting in front of a light box every day through the difficult season. Her data shows that long-term compliance is rare.

— Source: University of Vermont