Effectiveness of Light Therapy in Cognitively Impaired Persons: A Metaanalysis of Randomized Controlled Trials.

5 Repeated evidence

What this means for you: this is established.

Type of study: meta-analysis or systematic review
Studied in: people
Participants: not stated in the abstract
Published: 2017 in Journal of the American Geriatrics Society
Cited: 13 times by other research
Who paid: Not declared. PubMed carries no conflict-of-interest statement for most articles; that is not the same as independent.
Source: PubMed 28734045 · doi 10.1111/jgs.14990

The plain-language write-up of this study is still being written. Below is the abstract exactly as the researchers published it.

Abstract by the researchers — original text

OBJECTIVES: To explore the effects of light therapy on behavioral disturbances (BDs), sleep quality, and depression. DESIGN: Meta-analysis of randomized controlled trials. SETTING: PubMed, Cochrane Library, Medline, EMBASE, Web of Science, and clinicaltrials.gov of selected randomized controlled trials and previous systematic reviews were searched. PARTICIPANTS: Cognitively impaired persons. MEASUREMENTS: Information was extracted on study characteristics, quality assessment, and outcomes. Outcome measures included BDs, sleep quality, and depression. RESULTS: Nine randomized controlled trials were examined. The results showed that light therapy has a moderate effect on BD (g = -0.61) and depression (g = -0.58) and a small effect on total sleep time at night (g = 0.25). Subgroup analysis indicated that a light intensity of 2,500 lux or greater has a greater effect on depression than an intensity of less than 2,500 lux (P = .03), and the low risk of bias in blinding was superior to the RCTs deemed to be of high or unclear risk of bias in blinding in terms of BD (P = .02). CONCLUSION: Light therapy can relieve BD, improve sleep quality, and alleviate symptoms of depression for cognitively impaired persons.