New Study in Publication!
Congratulations to Drs. Melissa Armstrong and Steven DeKosky on the publication of “Associations among sleep quality, cognitive decline, and Alzheimer’s disease pathology in older adults: A longitudinal study,” which appears in the June issue of Alzheimer’s and Dementia.
Abstract
INTRODUCTION: This study aimed to investigate whether sleep quality predicts cognitive/functional decline, and whether Alzheimer’s disease (AD) pathology modifies these relationships.
METHODS: The Pittsburgh Sleep Quality Index was administered to 326 older adults (113 cognitively normal, 192 mild cognitive impairment, 21 dementia; mean age = 66.4 ± 8.0 years) enrolled in the 1Florida Alzheimer’s Disease Research Center. The Clinical Dementia Rating Sum of Boxes (CDR‐SB) assessed cognitive/functional decline at baseline and over time. Moderators included hippocampal volume (HV), amyloid beta (Aβ) positron emission tomography, and plasma phosphorylated tau (p‐tau)217.
RESULTS: Cross‐sectionally, longer sleep duration and later wake time were associated with worse CDR‐SB, with stronger associations observed among individuals with higher Aβ and p‐tau217 levels, and smaller HV. Longitudinally, prolonged sleep duration was associated with faster cognitive decline, particularly in individuals with elevated Aβ or p‐tau217 levels and smaller hippocampal volumes at baseline.
DISCUSSION: Prolonged sleep duration and later wake times predicted worsening cognitive performance, and these effects were strengthened by greater AD pathology.