Sleep Disturbance Forecasts β-Amyloid Accumulation across Subsequent Years

Area of Science:

• Neuroscience
• Sleep Science
• Biomarker Research

Background:

• Experimental sleep disruption in rodents and humans affects beta-amyloid (Aβ) dynamics.
• Impaired sleep structure may serve as a prospective biomarker for Aβ accumulation rates.

Purpose of the Study:

• To test if baseline non-rapid eye movement (NREM) sleep slow-wave activity (SWA) and sleep efficiency predict the rate of Aβ accumulation.
• To investigate objective sleep markers as potential biomarkers for longitudinal Aβ deposition.

Main Methods:

• Assessed clinically normal older adults using polysomnography for sleep measures.
• Tracked longitudinal Aβ accumulation using [11C]PiB positron emission tomography (PET) imaging.
• Analyzed the relationship between baseline sleep metrics and the rate of Aβ deposition.

Main Results:

• Lower NREM SWA (<1 Hz) and reduced sleep efficiency predicted faster Aβ deposition over time.
• These associations remained significant after controlling for age, sex, and sleep apnea.
• Other sleep architecture metrics did not show similar predictive sensitivity.

Conclusions:

• Objective sleep markers, specifically NREM SWA and sleep efficiency, can forecast longitudinal cortical Aβ deposition.
• Sleep measures may offer an affordable, scalable, and non-invasive tool for tracking Alzheimer's disease pathology progression.
• Sleep biomarkers could identify individuals at risk for Alzheimer's disease prior to cognitive symptom onset.