Longitudinal sleep duration patterns and their association with cognitive decline in older Chinese adults

INTRODUCTION: Associations between sleep duration and cognitive decline are inconsistent, and the value of longitudinal changes versus static measurements remains unclear. METHODS: We identified longitudinal sleep patterns in 4780 older adults from the Chinese Longitudinal Healthy Longevity Survey (CLHLS) using K-means clustering. Linear mixed-effects models and Cox models assessed cognitive decline and incident dementia risk over 10 years. RESULTS: The "Consistently Long" pattern showed the fastest cognitive decline (β = -0.027 standard deviation/year; p < 0.001) and highest cumulative dementia incidence. Conversely, patterns trending toward healthy duration slowed decline. However, adjusted Cox models found no significant association between sleep patterns and incident dementia risk. DISCUSSION: The trajectory of sleep duration, particularly the direction of change, is a powerful correlate of cognitive decline. Monitoring long-term dynamics outperforms static assessments for identifying high-risk older adults.