Efficacy of light therapy on nonseasonal depression among elderly adults: a systematic review and meta-analysis

Abstract

Objective

The aim of this study was to examine the effectiveness of light therapy in the treatment of geriatric depression.

Methods

A systematic review and meta-analysis were carried out. Data sources for the literature search were PubMed, Cochrane Collaboration’s Central Register of Controlled Clinical Trials, Cochrane Systematic Reviews, and ClinicalTrials.gov. Controlled trials of light therapy on older patients with nonseasonal depression and depression rating scales were eligible. Studies were pooled using a random-effect model for comparisons with light therapy. We used effect size (ES), which expresses changes in depression severity, in each selected meta-analysis to calculate the standardized mean difference on the basis of Hedges’ adjusted g; positive values indicated that the depression severity improved after light therapy. All results were presented with 95% CIs. Statistical heterogeneity was explored through visual inspection of funnel plots and the I² statistic. Moderators of effects were explored using meta-regression.

Results

We identified eight trials involving 395 participants that met the inclusion criteria. Light therapy was significantly more effective than comparative treatments, including placebo or dim light, with an ES of 0.422 (95% CI: 0.174–0.709, P=0.001). In addition, six of the eight trials used bright (white) light, resulting in significantly reduced severity of geriatric depression (N=273, ES: 0.460, 95% CI: 0.085–0.836, P=0.016). Furthermore, pale blue light therapy reduced the severity of geriatric depression (N=89, ES: 0.464, 95% CI: 0.046–0.882, P=0.030).

Conclusion

Our results highlighted the significant efficacy of light therapy in the treatment of geriatric depression. Additional well-designed, controlled studies are necessary to adopt standard parameters, adequate group sizes, and randomized assignment to evaluate more thoroughly the efficacy of light therapy for treating geriatric depression.

Keywords:

• depression
• elderly adults
• light therapy

View correction statement:

Efficacy of light therapy on nonseasonal depression among elderly adults: a systematic review and meta-analysis [Corrigendum]

Acknowledgments

This work was supported by grants from China Medical University Hospital (DMR-107-201) and the Ministry of Health and Welfare, Taiwan (MOHW107-TDU-B-212-123004).

Author contributions

Chun-Hung Chang proposed the research ideas, performed the statistical analysis, processed the database, and drafted the initial manuscript. Shaw-Ji Chen and Chieh-Yu Liu searched the database, provided expert opinions, and reviewed the final submitted manuscript. Hsin-Chi Tsai was in charge of this study, critically reviewed the draft of the manuscript, and approved the final submitted version of the manuscript. All authors contributed to data analysis, drafting and revising the article, gave final approval of the version to be published, and agree to be accountable for all aspects of the work.

Disclosure

The authors report no conflicts of interest in this work.