Meta-analysis finds bright light therapy boosts remission and response in nonseasonal depression, offering a low-cost add-on to standard care.
TRANSLATING RESEARCH INTO PRACTICE
Rajesh R. Tampi, MD, MS, DFAPA, DFAAGP, Column Editor
A monthly column dedicated to reviewing the literature and sharing clinical implications.
Major depressive disorder (MDD) is a critical mental health issue and a leading cause of functional disability. Initial treatment response rates in MDD are as low as 50% even when adequate doses of medication are trialed for a duration of 4 to 8 weeks. Bright light therapy (BLT) is a low-cost treatment shown to be effective as adjunct therapy for seasonal depressive disorders. Previously, there were few studies evaluating it for nonseasonal depressive disorders, but several recent trials evaluating BLT use as an adjunct treatment for nonseasonal depressive disorders have been published.
Menegaz de Almeida A, Aquino de Moraes FC, Cavalcanti Souza ME, et al.
No funding was reported.
To evaluate the efficacy of BLT as an adjunct treatment for nonseasonal depressive disorders.
This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guidelines. A systematic search of the MEDLINE, Embase, SCOPUS, Web of Science, PsycINFO, and CENTRAL databases was conducted for studies from inception to March 25, 2024. The search strategy used the key words bright light AND either unipolar or bipolar or depression or depressive AND augmentation or adjunctive or adjunct or add-on.
Two independent authors screened article abstracts for relevance; full article review was then used to screen the remaining manuscripts for eligibility. Included studies were randomized clinical trials (RCTs) published after the year 2000. Eligible studies compared BLT alone, or BLT plus an antidepressant with either placebo, antidepressant monotherapy, or dim red light. BLT was defined as using a fluorescent light box that produced white light for at least 30 minutes (the common range was 10,000 lux). Studies were excluded if they lacked a control group, were published in a non-English language, or were conference abstracts.
Primary outcomes were treatment response and symptom remission. Secondary outcomes included the Hamilton Rating Scale for Depression (HAM-D), the Montgomery-Åsberg Depression Rating Scale (MADRS), and the Clinical Global Impressions Scale (CGI). A subgroup analysis was conducted that stratified different follow-up times to see how they affected remission rates and response rates. Risk of bias was assessed independently by 2 authors using using the Cochrane risk-of-bias tool.
All statistical analyses were completed using the RStudio software version 4.3.2 and extension package. Binary outcomes were assessed using OR. Continuous outcomes were evaluated using either mean difference (MD) or standard mean difference (SMD), both with 95% CI. Heterogeneity was evaluated using I2 statistics with 95% CI; significance was set at I2 > 25%. The Mantel-Haenszel random-effects model was applied to all outcomes. A meta-regression analysis evaluated whether age of onset or illness duration were associated with remission or response rates.
This systematic review and meta-analysis included 11 RCTs with a total of 858 participants. Of these, 649 were female (75.6%), and 209 were male (24.4%). A total of 426 participants received BLT (52.3%) and 389 received control treatment (47.7%). Ten studies occurred in the outpatient setting, whereas 1 study occurred in the inpatient setting. There were differences in BLT protocols across the studies (9 studies used 10,000 lux for 30-60 minutes daily, 1 study used 7000 lux for 60 minutes daily, 1 study used 5000 lux for 30 minutes daily).
The primary outcome analysis showed that BLT significantly improved remission rates compared with the control groups (40.7% vs 23.5%; OR, 2.42; 95% CI, 1.50-3.91). Bright light therapy also significantly improved treatment response rates compared with control (60.4% vs 38.6%; OR, 2.34; 95% CI, 1.46-3.75). A stratified subgroup analysis was performed based on duration of treatment. This demonstrated that benefits were apparent in both short-term (<4 weeks) and longer-term (>4 weeks) follow-up, with higher remission and response rates in the BLT group at both time points.
The secondary outcome analysis demonstrated that HAM-D scores showed statistically significant improvement with BLT compared with control (MD, −1.44 points; 95% CI, −2.40 to −0.48). No significant differences were observed for CGI scores (MD, −0.06; 95%CI, −0.29 to 0.16) or MADRS scores (MD, 0.36; 95% CI, −2.60 to 3.31).
1. This was a large, well-designed meta-analysis that included RCTs and a total of 858 participants.
2. The study demonstrated a transparent quality appraisal process and utilized appropriate inclusion criteria.
3. Clinically relevant outcomes were examined by focusing on treatment response and remission rates.
1. Heterogeneity of BLT protocols (light intensity, timing, duration of treatment, etc) limits internal validity.
2. Sample sizes of individual studies were generally small.
3. Included studies assessed only short-term results (up to 6 weeks).
4. Included trials were conducted in limited geographic regions; daylight differences may affect treatment outcomes.
BLT demonstrated efficacy as an adjunctive treatment for adults with nonseasonal depressive disorder. Adding BLT to standard treatment improved response and remission rates compared with standard treatment alone.
These findings support adding BLT to routine clinical management for patients with nonseasonal patterns of depressive disorders. This may be especially relevant for patients with an incomplete response to standard treatment or patients interested in nonpharmacologic treatment options.
BLT demonstrated efficacy as an adjunctive treatment for adults with nonseasonal depressive disorder, improving both response and remission rates when added to standard care.
Dr Leconte is a third-year psychiatry resident at Creighton University in Omaha, Nebraska. Dr Kubista is a fourth-year psychiatry resident at Creighton University. Dr Schuster is an assistant professor of psychiatry at Creighton University School of Medicine. Dr Mullen is an assistant professor of psychiatry at Saint Louis University School of Medicine in Missouri. Dr Tampi is a professor and the chair of the Department of Psychiatry at Creighton University School of Medicine and Catholic Health Initiatives Health Behavioral Health Services. He is also an adjunct professor of psychiatry at Yale School of Medicine in New Haven, Connecticut, and a member of the Psychiatric Times editorial board.
Reference
Menegaz de Almeida A, Aquino de Moraes FC, Cavalcanti Souza ME, et al.
4 days ago
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