Patient-Oriented Evidence That Matters
Light Therapy Improves Behavioral Disturbances, Sleep, Depression in Older Patients with Cognitive Impairment
Am Fam Physician. 2018 Feb 15;97(4):online.
Does light therapy improve sleep quality, depression, and behavioral problems in older patients who have cognitive impairment?
In this meta-analysis, older patients with cognitive impairment who were exposed to light therapy had moderate improvements in behavioral disturbances, small improvements in sleep quality, and moderate improvements in depression. The authors did not report data on responders vs. nonresponders or on the potential adverse effects of treatment. (Level of Evidence = 1a)
These authors systematically reviewed multiple databases and clinical trial registries to identify randomized trials that evaluated the effect of light therapy on behavioral disturbances, sleep quality, and depression in older patients with cognitive impairment. Two authors independently assessed the risk of bias for each included study. They had high inter-rater reliability (kappa = 0.9), and tried to resolve disagreements through discussion; they used a third member of the team when agreement was not possible. They ultimately included nine trials with a total of 416 patients. The degree of cognitive impairment—based on results from the Mini-Mental State Examination—ranged from 5.7 to 22.1. The intensity of light in the studies ranged from 210 to 10,000 lux, and most of the patients were treated in the morning. The duration of light therapy ranged from one to 10 weeks (average = 5.4 weeks). Most control groups were exposed to average-strength indoor light; one study used no specific light as a control. None of the studies were considered to be of high methodologic quality, with the lack of masking being the most common concern. The pooled data from the five studies that evaluated behavioral disturbances showed moderate improvement with no statistical evidence for publication bias. Six studies that evaluated sleep quality showed small improvements and no statistical evidence for publication bias. Five studies that evaluated depression showed moderate improvements and no statistical evidence for publication bias. The authors did not report on potential harms of therapy, but I suspect there were not many.
Study design: Meta-analysis (randomized controlled trials)
Funding source: Government
Setting: Outpatient (any)
Reference: Chiu HL, Chan PT, Chu H, et al. Effectiveness of light therapy in cognitively impaired persons: a metaanalysis of randomized controlled trials. J Am Geriatr Soc. 2017;65(10):2227–2234.
POEMs (patient-oriented evidence that matters) are provided by Essential Evidence Plus, a point-of-care clinical decision support system published by Wiley-Blackwell. For more information, please see http://www.essentialevidenceplus.com. Copyright Wiley-Blackwell. Used with permission.
For definitions of levels of evidence used in POEMs, see http://www.essentialevidenceplus.com/product/ebm_loe.cfm?show=oxford.
To subscribe to a free podcast of these and other POEMs that appear in AFP, search in iTunes for “POEM of the Week” or go to http://goo.gl/3niWXb.
This series is coordinated by Sumi Sexton, MD, Editor-in-Chief.
A collection of POEMs published in AFP is available at http://www.aafp.org/afp/poems.
Want to use this article elsewhere? Get Permissions
More in AFP
MOST RECENT ISSUE
Jan 15, 2020
Access the latest issue of American Family Physician