Abstract
BACKGROUND: SMRUTHI‐INDIA is a Cohort Multiple Randomized Controlled Trial (cmRCT) study examining risk and protective factors in preventing dementia. Globally, around 50 million adults are diagnosed with dementia, with India accounting for approximately 16% of these cases. Identifying protective factors, such as sleep quality, may help delay or prevent its onset. This study explores the potential protective role of sleep quality in maintaining cognitive health among the elderly. METHOD: This study employed a cmRCT design, allowing for repeated RCTs within an established cohort. The cohort was formed across four rural zones of India, focusing on dementia risk factors with annual neuropsychological assessments over five years. The current sample includes 2,402 individuals aged 55 and above. Sleep quality and cognition were assessed using the Pittsburgh Sleep Quality Index (PSQI) and Addenbrooke’s Cognitive Examination III (ACE‐III). Sex‐based comparisons were analysed using the Wilcoxon Rank‐Sum test. RESULT: Of 2,402 participants, 61.62% were females. Based on PSQI scores, 1,981 participants (83%) had good sleep quality (PSQI < 5), where data of 14 females and 10 males was not available due to lack of consent. Among females, 1,183 had good sleep quality; among males, 798 had good sleep quality. Cognitive performance, measured using ACE‐III, was compared across sleep quality groups using Wilcoxon Rank‐Sum test. In males, poorer sleep quality was significantly associated with lower cognitive scores (p = 0.01). However, no significant association was observed in females (p = 0.7), indicating a potential sex‐specific difference in the relationship between sleep quality and cognitive function. CONCLUSION: The findings of current study suggest that poor sleep quality is significantly associated with reduced cognitive performance in elderly males but not in females, highlighting a possible sex‐specific difference in how sleep affects cognitive health. These results underscore the importance of considering gender‐specific approaches when designing interventions to preserve cognitive function and potentially prevent dementia in aging populations. Further longitudinal analysis may help clarify the underlying mechanisms and long‐term impact of sleep quality on cognitive decline.