Green Amit1,2*, Kamer Lilach1, Dagan Yaron1,2,3 and Cohen-Zion Mairav1,4
1Department of Neurobiology, Sleep and Fatigue Institute, Israel
2Department of Neurobiology, Research Institute of Applied Chronobiology, Israel
3Department of Neurobiology, University of Haifa Mount Carmel, Israel
4Department of Neurobiology, School of Behavioral Sciences, Israel
Aging is associated with sleep difficulties, including insomnia, lighter more fragmented sleep and advanced sleep phase. These sleep problems have been linked with fatigue, cognitive deficits, reduced Quality of Life (QoL), and increased health risks in the elderly. This study examined non-invasive light treatment administered in a residential group format to examine whether such a treatment paradigm is feasible and beneficial for sleep and daytime function. We conducted a randomized, placebo-controlled, 2x2 mixed study design. Seventeen healthy older adults [12F and 5M, 81.5(± 9.3) years, BMI 26.2(± 3.2)]. All participants underwent 5 consecutive days of 2 hours/day of “typical” light exposure (500-1000lux, 09.00-11.00) in a designated common room. They were then randomized to treatment (T; n=12; 3000-5000lux) or control (C; n=5; “treatment as usual”: 500-1000lux) groups, and repeated the above protocol, with the respective light intensity. Participants wore actigraphs throughout the study and at the end of each exposure period, conducted a computerized neuropsychological battery and filled out questionnaires. We observed reduction in objective Sleep Onset Latency (SOL) in the T vs C. The improve in global cognitive and memory scores was greater in T vs C. In the environmental health-related QoL we found greater improvement in T vs C. Continuous morning light exposure seems to primarily affect cognitive functioning, specifically memory ability. Interestingly, participants also reported increased satisfaction with their environmental well-being, including their home environment and recreation. This innovative, non-invasive approach to light administration is feasible and may have wide-ranging applicability for older adults living in residential facilities.
Amit G, Lilach K, Yaron D, Mairav C-Z. Functional Consequences of Light Treatment in Healthy Older Adults Living in Residential Facility. Ann Sleep Med Res. 2018;2(1):1010 .