Effect of Blue Light Exposure on Sleep and Cognition in Stroke: A Randomized Controlled Study
Faculty Mentor
Elena Crooks
Presentation Type
Poster
Start Date
4-14-2026 9:00 AM
End Date
4-14-2026 11:00 AM
Location
PUB NCR
Primary Discipline of Presentation
Physical Therapy
Abstract
BACKGROUND & PURPOSE: Blue light exposure (BLt) is a promising non-pharmacological intervention for improving sleep and alertness, but its efficacy in acute stroke remains unclear. This study examined whether morning BLt improves daytime sleepiness, cognition, and sleep among participants receiving inpatient rehabilitation (IR) for acute stroke. METHODS: Forty-three participants receiving IR post-acute stroke (age 66.2 ± 14.1 years) completed the study. Participants were randomized to red light (RLt; n=22) or BLt (n=21). At baseline (BL; 08:00-09:00) participants completed the Karolinska Sleepiness Scale (KSS) and Rey Auditory Verbal Learning Test (RAVLT). The following day, participants received 25 min of BLt or RLt at 08:00, repeated daily until one day prior to study discharge. At study discharge (DC), outcome measures were reassessed and relative change scores were calculated. Wrist actigraphs measured time to fall asleep (TFA), nighttime sleep duration (NSD), and number of nighttime awakenings (NNAs). Analyses included generalized linear and linear mixed models (SPSS v. 29). RESULTS: Mean days of light exposure did not differ between groups (p=0.93). BLt produced greater improvements in KSS (0.35 vs 0.03; p=0.001) and RAVLT (0.95 vs -0.05; p< 0.001). Groups did not differ in BL sleep measures. During the intervention phase, BLt significantly reduced TFA (14.1 vs 54.3 min; p<0.001) and trended towards longer NSD and fewer NNAs (p=0.09). CONCLUSIONS: Morning BLt improves daytime sleepiness and cognition in participants post-acute stroke. BLt is a safe, feasible intervention for improving alertness and cognition during acute stroke IR. Further research should examine long-term and functional outcomes.
Recommended Citation
Craner, Kaden, "Effect of Blue Light Exposure on Sleep and Cognition in Stroke: A Randomized Controlled Study" (2026). 2026 Symposium. 1.
https://dc.ewu.edu/srcw_2026/ps_2026/p1_2026/1
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Effect of Blue Light Exposure on Sleep and Cognition in Stroke: A Randomized Controlled Study
PUB NCR
BACKGROUND & PURPOSE: Blue light exposure (BLt) is a promising non-pharmacological intervention for improving sleep and alertness, but its efficacy in acute stroke remains unclear. This study examined whether morning BLt improves daytime sleepiness, cognition, and sleep among participants receiving inpatient rehabilitation (IR) for acute stroke. METHODS: Forty-three participants receiving IR post-acute stroke (age 66.2 ± 14.1 years) completed the study. Participants were randomized to red light (RLt; n=22) or BLt (n=21). At baseline (BL; 08:00-09:00) participants completed the Karolinska Sleepiness Scale (KSS) and Rey Auditory Verbal Learning Test (RAVLT). The following day, participants received 25 min of BLt or RLt at 08:00, repeated daily until one day prior to study discharge. At study discharge (DC), outcome measures were reassessed and relative change scores were calculated. Wrist actigraphs measured time to fall asleep (TFA), nighttime sleep duration (NSD), and number of nighttime awakenings (NNAs). Analyses included generalized linear and linear mixed models (SPSS v. 29). RESULTS: Mean days of light exposure did not differ between groups (p=0.93). BLt produced greater improvements in KSS (0.35 vs 0.03; p=0.001) and RAVLT (0.95 vs -0.05; p< 0.001). Groups did not differ in BL sleep measures. During the intervention phase, BLt significantly reduced TFA (14.1 vs 54.3 min; p<0.001) and trended towards longer NSD and fewer NNAs (p=0.09). CONCLUSIONS: Morning BLt improves daytime sleepiness and cognition in participants post-acute stroke. BLt is a safe, feasible intervention for improving alertness and cognition during acute stroke IR. Further research should examine long-term and functional outcomes.