Bright White Light Therapy Promising for Bipolar Depression
Midday bright light sessions associated with higher remission rate than dim red placebo light treatment
MONDAY, Oct. 16, 2017 (HealthDay News) -- Midday bright light therapy may be effective for treating bipolar depression, according to a study published online Oct. 3 in The American Journal of Psychiatry.
Dorothy K. Sit, M.D., from Northwestern University in Chicago, and colleagues randomly assigned participants (depressed adults with bipolar I or II disorder who were receiving stable dosages of antimanic medication) to treatment with either 7,000-lux bright white light or 50-lux dim red placebo light (23 participants in each group). They received daily treatment at midday for six weeks, and symptoms were assessed weekly.
The researchers found that the group treated with bright white light experienced a significantly higher remission rate than the placebo light group (68.2 versus 22.2 percent; adjusted odds ratio, 12.6) during weeks 4 to 6. The bright white light group also had significantly lower depression scores at the endpoint visit. There were no mood polarity switches. Sleep quality improved and was similar in both groups.
"The data from this study provide robust evidence that supports the efficacy of midday bright light therapy for bipolar depression," conclude the authors.