Effect of bright-light therapy on depression and anxiety of a patient with Alzheimer's disease combined with sleep disorder: A case report.

Background: Alzheimer's disease (AD) is a common type of dementia due to neuronal impairment. In addition, psychobehavioral symptoms including severe sleep disorders, depression and anxiety can occur in most patients with AD.

Case summary: We report a case of a 68-year-old woman with a 2-year history of AD. She initially presented with memory loss, progressively more severe, leading to a depressive and anxious status. The clinical symptoms also included severe sleep disturbances. Considering the age and health state of the patient, a non-pharmacological treatment of bright light therapy was used to improve her sleep quality. The treatment was provided for 30 minutes twice a day, during 8:30 am to 9:00 am and 16:30 pm to 17:00 pm. After 4 weeks of therapy, the sleep quality notably improved, with a marked decrease in daytime sleep, increase in nighttime sleep, and disappearance of nocturnal activity. The depression and anxiety were also suppressed significantly.

Conclusion: This case report suggested that bright light therapy can have a positive effect on sleep quality in elderly patients with AD and can be used as an effective and safe non-pharmacological treatment.