Study shows benefit of tailored lighting to older, ADRD adults in living facilities

A clinical trial has proven that exposure to tailored, circadian-effective light can have a positive effect on sleep patterns, moods and behaviors of patients with Alzheimer disease and related dementias (ADRD) living in long-term or assisted-living facilities.

Older adults with ADRD typically experience major problems with sleep-wake and rest-activity patterns, leaving them at risk for a poor quality of life. Symptoms include confusion, wandering at night, irritability and agitation, reversal of day-and-night habits, decreased cognitive functioning, and depression, particularly at the onset of night (also known as sundowners syndrome).

A downward spiral results when, because of the symptoms, they are homed in controlled, senior-living environments where they experience even less activity and less exposure to the sun or to circadian-friendly lighting. According to the study results, “a circadian-effective lighting intervention can ameliorate these symptoms.”

In summarizing the study’s purpose, the authors wrote:

“The study’s primary aim was to extend our earlier studies and determine whether a TLI (tailored lighting intervention) delivering a high level of circadian stimulation would improve reported and objective measures of nighttime sleep. The secondary aim was to determine whether the TLI would improve caregiver-assessed participant scores in measures of depression, agitation, and quality of life. It was hypothesized that all-day exposure to the TLI would significantly improve objective and reported measures of sleep in participants. We also hypothesized that the active TLI would improve reported measures of depression, agitation, and quality of life.”

Highlights from the study’s results follow:

  • “In this randomized, placebo-controlled, crossover design field study, it was demonstrated that a TLI designed to maximally affect the circadian system improved reported measures of sleep quality, depression, and agitation behavior in participants with moderate to late-stage ADRD.”
  • “With respect to the study’s secondary aim, the present results showed a significant improvement in depression scores for the active lighting intervention.”
  • “The present results demonstrate that exposures tailored to maximally entrain the circadian system, especially when carefully delivered and measured in the field, can significantly improve sleep quality, depressive symptoms, and agitation behavior in patients with ADRD. The light was also well tolerated by the participants, which is crucial for the effective delivery of a lighting intervention in real-world applications. The next step is to investigate the most appropriate dose (i.e., duration and timing of light exposure) to more effectively deliver the stimulus.”

The 14-week study involved 46 subjects in eight facilities for two, non-concurrent four-week periods. It was conducted by a group of doctors and scientists: Mariana G. Figueiro, PhD; Barbara Plitnick, RN; Charles Roohan, BS; Levent Sahin, PhD; Michael Kalsher, PhD; and Mark S. Rea, PhD.

Find a full report on the study here.