Bright Light Treatment Effective for Non-Seasonal Major Depressive Disorder
CHICAGO -- November 18, 2015 -- Bright light treatment either alone or combined with an antidepressant was effective for adults with non-seasonal major depressive disorder (MDD), according to a study published online by JAMA Psychiatry.
Raymond W. Lam, MD, University of British Columbia, Vancouver, British Columbia, and colleagues conducted a double-blind test the efficacy of light treatment alone and in combination with fluoxetine hydrochloride compared with a placebo.
The 8-week trial randomised 122 patients to light therapy (30 minutes/daily exposure to a fluorescent light box as soon as possible after awakening plus a placebo tablet (n = 32); fluoxetine 20 mg/day plus a placebo device (a negative ion generator; n = 31); combination light and fluoxetine treatment (n = 29); or placebo device and placebo tablet (n = 30).
The change in a common depression rating scale score was the study’s primary outcomes.
Results showed that fluoxetine plus light therapy and light therapy alone were superior to placebo, but fluoxetine alone was not superior to placebo.
Why light therapy appears to work is still unknown but hypotheses in seasonal affective disorder involve resynchronising circadian rhythms. Non-seasonal MDD may also be associated with disturbances in the circadian rhythms, the authors noted.
One of the study’s limitations was the fact that researchers did not measure patients’ natural light exposure.
“Further studies exploring mediators and moderators of response will be important,” the authors concluded.
SOURCE: JAMA Psychiatry