Home-Based Tailored Light Therapy for Sleep, Mood, and Cognitive Outcomes in Mild Cognitive Impairment: A Randomized Trial

Background Light offers a promising approach to sleep and circadian disturbances in mild cognitive impairment (MCI). Objective Test a home-based lighting intervention in people living with MCI. Methods In a randomized, placebo-controlled trial, 61 participants received active or placebo light for 24 weeks, with assessments for cognition, sleep, depression, and quality of life at baseline, week 13, 25, and, post-intervention, at week 37. Light exposure was measured as area under the curve (AUC) for morning circadian stimulus (CS). Results Active light participants (mean age 69.7 years; 52% male; mean MoCA 21.4) showed greater improvement in ADAS-Cog memory scores than placebo ( p = 0.035), higher morning CS AUC by week 25 (0.021 vs −0.030; p = 0.025), and better sleep percent (−0.21 vs −1.29; p = 0.042), wake percent (−0.10 vs 1.19; p = 0.023), and wake after sleep onset (2.19 vs 8.23 min; p = 0.031).