Effectiveness of Light Therapy in Cognitively Impaired Persons: A Metaanalysis of Randomized Controlled Trials.
Study Goal
The researchers aimed to determine the effects of light therapy on behavioral disturbances, sleep quality, and depression in cognitively impaired individuals.
Results Summary
Light therapy showed moderate effects on reducing behavioral disturbances and depression, and a small effect on improving total sleep time at night. Higher light intensity (≥2,500 lux) was more effective for depression, and studies with low risk of bias in blinding showed better outcomes for behavioral disturbances.
Population
Cognitively impaired persons
Effective Dosage
Light intensity of 2,500 lux or greater (specific frequency not mentioned)
Duration
Not specified
Interactions
None mentioned
| Intervention | Direction | Endpoint | Population | Dosage | Impact | Claim # |
|---|---|---|---|---|---|---|
light therapy | decrease | behavioral disturbances | cognitively impaired persons | g = -0.61 | has a moderate effect on | #1 |
light therapy | decrease | depression | cognitively impaired persons | g = -0.58 | has a moderate effect on | #2 |
light therapy | increase | total sleep time at night | cognitively impaired persons | g = 0.25 | has a small effect on | #3 |
light therapy with intensity of 2,500 lux or greater | decrease | depression | cognitively impaired persons | P = .03 | has a greater effect on | #4 |
light therapy with low risk of bias in blinding | decrease | behavioral disturbances | cognitively impaired persons | P = .02 | was superior to RCTs with high or unclear risk of bias in blinding in terms of | #5 |
light therapy | decrease | behavioral disturbances | cognitively impaired persons | - | can relieve | #6 |
light therapy | increase | sleep quality | cognitively impaired persons | - | can improve | #7 |
light therapy | decrease | depression | cognitively impaired persons | - | can alleviate symptoms of | #8 |
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.