0334 Vitamin D Supplement Intake Linked to Increased Time Spent in the REM Dream-Stage in Persons with Sleep Disturbance and Mild Cognitive Impairment

Introduction Understanding how vitamin D supplementation relates to rapid eye movement (REM) sleep is important as both sleep disturbance and vitamin D deficiency is common in individuals with mild cognitive impairment (MCI) and may contribute to cognitive decline. Although some studies suggest that Vitamin D may improve sleep quality, findings are mixed. Vitamin D supplementation's effects on specific sleep architecture measures-particularly REM sleep, which is critical for memory consolidation, are not well understood. This study explored associations between vitamin D supplement intake and time spent in REM sleep among individuals with MCI and sleep disturbance. Methods This cross-sectional study included 36 participants with diagnosed or suspected MCI and symptoms of disturbed sleep (as identified by the Epworth Sleepiness Scale and/or Pittsburgh Sleep Quality Index). Vitamin D supplement intake was assessed using a modified Food Frequency Questionnaire (FFQ). Time spent in REM sleep was collected using an at-home polysomnography device (Sleep Profiler) and was averaged over two days. A multiple linear regression model examined the association between vitamin D supplement intake and minutes spent in REM sleep, controlling for baseline covariates of age, sex, body mass index (BMI), race, and history of hypertension. Results Participants had a mean age of 67.6 years (SD=1.5), a mean BMI of 28.8 (SD=7.1), 36.1% were male, and 33.3% with a history of hypertension. Daily Vitamin D supplements in the dosage range of 2000-4999 IU showed a significant increase in time spent in REM (estimate (SE) = 49.2 (22.1); p = 0.036). Conclusion To our knowledge, this is the first study to evaluate the relationship between daily vitamin D supplement intake and time spent in REM sleep in individuals with sleep disturbance and MCI. We found that moderate-dose vitamin D supplementation was associated with longer time spent in REM sleep in this population. Support (if any)