Importance: Bright light therapy is an evidence-based treatment for seasonal depression, but there is limited evidence for its efficacy in nonseasonal major depressive disorder (MDD).
Objective: To determine the efficacy of light treatment, in monotherapy and in combination with fluoxetine hydrochloride, compared with a sham-placebo condition in adults with nonseasonal MDD.
Design, setting, and participants: Randomized, double-blind, placebo- and sham-controlled, 8-week trial in adults (aged 19-60 years) with MDD of at least moderate severity in outpatient psychiatry clinics in academic medical centers. Data were collected from October 7, 2009, to March 11, 2014. Analysis was based on modified intent to treat (randomized patients with ≥1 follow-up rating).
Interventions: Patients were randomly assigned to (1) light monotherapy (active 10,000-lux fluorescent white light box for 30 min/d in the early morning plus placebo pill); (2) antidepressant monotherapy (inactive negative ion generator for 30 min/d plus fluoxetine hydrochloride, 20 mg/d); (3) combination light and antidepressant; or (4) placebo (inactive negative ion generator plus placebo pill).
Main outcomes and measures: Change score on the Montgomery-Åsberg Depression Rating Scale (MADRS) from baseline to the 8-week end point. Secondary outcomes included response (≥50% reduction in MADRS score) and remission (MADRS score ≤10 at end point).
Results: A total of 122 patients were randomized (light monotherapy, 32; fluoxetine monotherapy, 31; combination therapy, 29; placebo, 30). The mean (SD) changes in MADRS score for the light, fluoxetine, combination, and placebo groups were 13.4 (7.5), 8.8 (9.9), 16.9 (9.2), and 6.5 (9.6), respectively. The combination (effect size [d] = 1.11; 95% CI, 0.54 to 1.64) and light monotherapy (d = 0.80; 95% CI, 0.28 to 1.31) were significantly superior to placebo in the MADRS change score, but fluoxetine monotherapy (d = 0.24; 95% CI, -0.27 to 0.74) was not superior to placebo. For the respective placebo, fluoxetine, light, and combination groups at the end point, response was achieved by 10 (33.3%), 9 (29.0%), 16 (50.0%), and 22 (75.9%) and remission was achieved by 9 (30.0%), 6 (19.4%), 14 (43.8%), and 17 (58.6%). Combination therapy was superior to placebo in MADRS response (β = 1.70; df = 1; P = .005) and remission (β = 1.33; df = 1; P = .02), with numbers needed to treat of 2.4 (95% CI, 1.6 to 5.8) and 3.5 (95% CI, 2.0 to 29.9), respectively. All treatments were generally well tolerated, with few significant differences in treatment-emergent adverse events.
Conclusions and relevance: Bright light treatment, both as monotherapy and in combination with fluoxetine, was efficacious and well tolerated in the treatment of adults with nonseasonal MDD. The combination treatment had the most consistent effects.
Trial registration: clinicaltrials.gov Identifier: NCT00958204.