Date Presented 04/22/2023

Circadian lighting, indoor light that simulates the solar day, was explored as a means to help regulate sleep in a person living with dementia and a college student. Results indicate that a daily, 1-hour circadian lighting exposure helped to regulate sleep and improve mood and engagement for both cases. Implementation was facilitated by integrating lighting into a daily leisure or instrumental routine. Findings contribute to OT knowledge on means to promote the occupation of sleep.

Primary Author and Speaker: Martha Sanders

Contributing Authors: Samantha Barnaba, Luke Bowerman, Kayla Cicero, Alexandra Muzzio, Alexis Silverstein, Taylor Demarco

PURPOSE AND IMPORTANCE: Dysregulated sleep is a public health concern across multiple populations including persons living with dementia and college students. Optimal sleep is fundamental to good health and full participation in daily living. OTPs provide sleep hygiene education; however, the use of lighting to set circadian rhythms and promote sleep has yet to be studied despite OTs focus on environmental modifications. Circadian lighting refers to indoor lighting that parallels sun patterns with bright light in the morning, dim light in evenings, and darkness at night. Robust patterns of light and darkness promote healthy sleep and daily alertness by syncing the body’s circadian rhythms with the solar day. This study explored the use of circadian lighting in two cases.The research questions were: 1) What is the impact of circadian lighting interventions on sleep, mood, and engagement, in a person living with dementia and a college student; and, 2) How do participants integrate circadian lighting into their daily routines?

DESIGN: This mixed-method case study used repeated pretest/post-tests measures and semi-structured weekly interviews over a 5-week period. Inclusion criteria were having dysregulated sleep and not using sleeping aids. Additional criteria for the person with dementia were a confirmed diagnosis, a regular caretaker, and age of 65 or older; the college student must have been18 and live in a dorm or apartment.

METHOD: Participants completed pretest measures in Week 1: Pittsburgh Sleep Quality Index [PSQI), Cornell Scale for Depression in Dementia [CSDD] or Profile of Mood States[POMS-A], and the Engagement in Persons with Dementia Scale [EPWDS]) or Utrecht Work Engagement Scale [UWES-9]). Participants also wore a fitness tracker to measure sleep duration and steps.

INTERVENTION: Participants used a Verilux Happy Light Luxe lightbox (>500 lux at the eye, 5000 CCT) in the morning for 1 hour daily for four weeks and recorded total duration and activities completed during exposure. In Week 5, participants completed post-tests, a sleep log, and wore the fitness tracker. Weekly check-ins determined challenges and facilitators of the implementation process along with a final interview on implementation.

RESULTS: Both cases presented with highly dysregulated sleep, poor mood/depression, and decreased productivity/engagement in daily activities. For Ester (sic), the person living with dementia, PSQI score improved 50% from 17/42 to 8.5/42 to reflect improves sleep regulation; depression scores decreased from 23/57 to 12/57. Engagement scores improved each week (25/40 to 34/40) to show increased interaction during the puzzle activity. Sleep became regulated by staying alert during the day and less time in bed (without sleeping). Caregiver reported consistent use of the light each morning while doing a puzzle activity. For Jean (sic), the college student, sleep scores improved 50% from 16/42 to 8/42. Mood stabilized improved from 106 to 86 with improvement in tension, anger, fatigue, and depression. Productivity for classwork improved for absorption and dedication. Jean reported earlier onset of sleep and more regular wake-up times. Implementation was facilitated by integrating the light into morning self-care, clearing, and studying routines. She reported improved academic performance and morning productivity.

CONCLUSION: Circadian lighting improved sleep regulation, mood, and engagement/productivity in two cases studies. Impact. This study expands our understanding of feasible approaches to promote sleep regulation through the environmental modification of lighting A daily lighting exposure can be realistically integrated into daily routines during a leisure, self-care, or instrumental activity.


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