The effect of bright light therapy on major depressive disorder: A systematic review and meta-analysis of randomised controlled trials.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of randomized controlled trials
PubMed 39067131 · doi:10.1016/j.ajp.2024.104149
What was done
Systematic review and meta-analysis of 15 randomised controlled trials (published 1996–2024) comprising 883 patients with non-seasonal major depressive disorder (MDD) identified across five databases. The primary outcome was endpoint depression score between bright light therapy (BLT) and control groups (standardised mean difference, SMD). Secondary outcomes included remission and response rates. Subgroup analyses evaluated the effects of trial duration and daily exposure length.
What was found
BLT significantly reduced depression scores compared to control treatments (SMD = 0.48, 95% CI [0.22, 0.74], p < 0.001). Trials lasting 2 weeks or less and protocols using 60 minutes or more of daily exposure showed higher therapeutic effectiveness. BLT was also associated with higher response rates, but exact numerical values, odds ratios, and remission rates were not reported in the abstract.
Why it matters
Bright light therapy appears to be an accessible, non-invasive adjunctive intervention for non-seasonal depression that can augment standard pharmacotherapy and psychotherapy.
Limits
The combined sample size across 15 trials was modest (883 participants). The abstract omits exact effect estimates for binary outcomes (response, remission), details on control sham conditions, risk of bias assessments, adverse events, and post-treatment follow-up duration.
Cited by
- supports Bright light exposure is effective for treating non-seasonal depression.