The effect of light therapy on the sleep quality of the elderly: An intervention study

Objective: The study was conducted to determine the effect of light therapy on the sleep quality of older adults. Design: This interventional study was conducted with a single group pre-test, post-test model. Setting The study was conducted in a nursing home in Ankara, Turkey. Subjects Twenty-four older adults with poor sleep quality were included in the study. Intervention During the study procedure, a 10,000 Lux light was administered continuously for a half-hour duration in the morning over a one-month period. Main outcome measures The main outcome measures included global and subcomponents of sleep quality, which were assessed by the Pittsburgh Sleep Quality Index, and were repeatedly measured at the baseline, pre-intervention (four weeks at baseline), post-intervention (at the end of intervention/eight weeks at baseline), and follow-up (four weeks at intervention). Results: At the end of light therapy intervention and during the four-week follow-up period, the global sleep quality scores were found to be higher compared with pre-intervention and baseline scores (p < 0.001). The 'daytime dysfunction' and 'sleep latency' sub-scores were found to be the most positively changed, whereas the change in 'duration of sleep' sub-score was less. Conclusion: Light therapy has been shown to be effective non-pharmacological therapy for improving sleep quality among healthy elders.