PriMera Scientific Medicine and Public Health (ISSN: 2833-5627)

Review Article

Volume 8 Issue 5

The Efficacy of Bright Light Therapy in Older Adults with Dementia - A Narrative Review

Spandana Charles*, Anum Abbas, Zainab Khan, Hira Habib, Naznin Naher, Muhammad Haris Latif, Hafiza Madhila Aslam and Kanwal Maheswari

May 09, 2026

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Abstract

Background: Dementia is a chronic condition that can have a significant burden on individuals and their caregivers. It poses a global challenge as 55 million people in the world live with this condition. Adults with dementia develop sleep problems and significant behavioral and psychological problems. Although medication is used to treat these symptoms, its use is associated with high-risk side effects like daytime somnolence and increased risk of falls. The administration of bright light therapy (BLT), which is a non-pharmacological therapy, can treat sleep disorders and can be an effective adjunct therapy. However, despite established proof regarding the potential use of light to treat sleep and behavioral disturbances of dementia, we do not have definitive protocols for administration of BLT.

Method: This study is a narrative review identifying and summarizing various studies done to study the efficacy of bright light therapy on patients with dementia. This was done so we could compare the different protocols, the type of light used, the duration of therapy and the positive and negative outcomes of each of these studies.

Results: We compared 14 studies conducted on older adults with dementia, most of them residing in facilities (some residing at home) exposing them to bright light of varying intensities (2500 lux- 10,000 lux) for a duration between 2 weeks to 24 weeks using light boxes, dynamic light therapy or simply by increasing indoor daylight exposure. We noticed that BLT was associated with an improvement in sleep efficiency along with reduced behavioral and psychological symptoms in almost all the studies.

Conclusion: BLT could be an effective strategy to treat dementia when properly designed and implemented.

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