Light Therapy in PALTC Can Help Sleep Rhythms, But Results Depend on Various Factors

January 10, 2023

January 10, 2023

Contact: Ellen Mullally

Light can regulate sleep rhythms, but the efficiency of light therapy remains controversial. A new study in the January issue of JAMDA summarized the current evidence and determined that the efficacy of light therapy in post-acute and long-term care (PALTC) settings may be affected by the duration of exposure, time and length of intervention, intensity of light, and equipment used to administer the therapy.

In Light Therapy to Improve Sleep Quality in Older Adults Living in Residential Long-Term Care: A Systematic Review, the authors looked at 21 articles summarizing light therapy with different durations and intensities. They found that the light intervention was typically administered between 7:00 PM and 12:00 AM  for 30-120 minutes. The interventions lasted from one week to several months, and the intensity of the light interventions usually ranged from 2,500 to 10,000 lux. The authors said the literature suggests that lighting intensity should be increased for more serious sleep disorders. They also observed that the wavelength of light is another important factor in light therapy.

“Taken together, these studies of light therapy suggest that it has variable but usually positive effects on sleep quality and circadian rhythms in residents living in long-term care settings,” said the authors. “Very few studies have reported adverse reactions after light therapy.” They further noted that future studies should include relatively large samples, longer interventions, and suitably longer follow-up, preferably with a randomized design. “Rigorous procedures will be crucial for optimizing the various parameters of light therapy, including intensity, wavelength, duration, and timing,” they said.

The study was conducted by researchers at the School of Nursing, Chengdu Medical College, Chengdu, Sichuan, China; Menzies Health institute Queensland & School of Nursing and Midwifery, Griffin University Nathan Campus, Brisbane, Queensland, Australia; Mental Health Center and National Clinical Research Center for Geriatrics, West China Hospital, Sichuan University, Chengu, Sichuan, China.

Get more information on the findings above and more details about the study. To contact the researchers or JAMDA editors for an interview, please email





JAMDA is the official journal of AMDA – The Society for Post-Acute and Long-Term Care Medicine. JAMDA publishes peer-reviewed articles including original studies, reviews, clinical experience articles, case reports, and more, on all topics more important to post-acute and long-term care medicine. Visit for more information.


About AMDA – The Society for Post-Acute and Long-Term Care Medicine

AMDA – The Society for Post-Acute and Long-Term Care Medicine is the only medical specialty society representing the community of over 50,000 medical directors, physicians, nurse practitioners, physician assistants, and other practitioners working in the various post-acute and long-term care (PALTC) settings. Dedicated to defining and improving quality, we advance our mission through timely professional development, evidence-based clinical guidance, and tireless advocacy on behalf of members, patients, families, and staff. Visit for more information.