Subjective sleep characteristics in non‐demented adults: domain‐specific associations with multimodal Alzheimer's disease biomarkers

Abstract INTRODUCTION Sleep problems are early features of Alzheimer's disease (AD). We examined domain‐specific associations of subjective sleep with cognition, brain networks, and AD biomarkers in non‐demented older adults. METHODS We studied 849 non‐demented participants from the Chinese Preclinical Alzheimer's Disease Study (CPAS) cohort. Subjective sleep dimensions were assessed, along with cognition, resting‐state functional magnetic resonance imaging, [ 18 F]‐florbetapir positron emission tomography, and plasma AD biomarkers. Associations were examined using adjusted general linear models RESULTS Most sleep characteristics worsened across the cognitive continuum except for duration. Sleep quality, efficiency, and daytime dysfunction were linked to poorer cognition, altered networks, and higher Aβ/tau levels. In contrast, sleep duration and disturbances showed paradoxical associations with plasma biomarkers. Use of sleep medication was related to better cognition and memory. DISCUSSION Adequacy‐ and function‐related sleep dimensions aligned with AD‐related decline, whereas quantity‐ and fragmentation‐related dimensions reflected network changes or subjective–objective discrepancies, suggesting distinct biological underpinnings of different sleep problems. Highlights Different subjective sleep dimensions show distinct links with cognition and AD biomarkers. Sleep quality, efficiency, and daytime dysfunction relate to cognition, networks, and Aβ/tau. Shorter sleep and greater fragmentation show paradoxical associations with plasma biomarkers. Sleep alterations may involve heterogeneous biological pathways in the AD continuum. Multidimensional sleep assessment may improve early detection and risk stratification in AD.