Prolonged morning wake transitions associated with amyloid beta burden: A cross-sectional pilot study.

INTRODUCTION

Sleep quality critically influences amyloid beta (Aβ) clearance, yet the specific role of morning wake transition duration remains unexplored.

METHODS

This hypothesis-driven secondary analysis examined 97 cognitively unimpaired older adults (mean age ± SD: 74.4 ± 5.8 years) who underwent 14-day actigraphy and 18F-florbetapir positron emission tomography (PET). Cognitive function was evaluated using the National Center for Geriatrics and Gerontology-Functional Assessment Tool (NCGG-FAT). Time to wake up (TWU) was calculated as the midpoint between initial wake and final rise times.

RESULTS

Binomial logistic regression models adjusted for age, depression, and sleep duration showed that extended TWU (>6.23 min) associated with higher Aβ positivity (27.1% vs 10.2%, odds ratio [OR] = 1.85, 95% confidence interval [CI]: 1.11-3.07, p = 0.019) and impaired word memory (OR = 2.17, 95% CI: 1.11-4.24, p = 0.023). Exploratory analyses of additional cognitive domains showed no significant associations.

DISCUSSION: Prolonged morning wake transitions may represent a behavioral marker associated with Aβ accumulation and memory impairment. The cross-sectional design and modest sample size warrant cautious interpretation and replication in larger longitudinal cohorts.