Sleep complaints and cerebral white matter: A prospective bidirectional study

Area of Science:

• Neuroscience
• Gerontology
• Sleep Medicine

Background:

• Sleep complaints and white matter changes are common in older adults.
• The temporal relationship between sleep issues and brain pathology is unclear.

Purpose of the Study:

• To investigate the prospective, bi-directional association between subjective sleep complaints and cerebral white matter integrity in aging.
• To determine if sleep complaints precede or follow white matter micro- and macro-structural changes.

Main Methods:

• Longitudinal, population-based cohort study with 2529 participants (aged 56±6 years).
• Assessed sleep complaints using the Pittsburgh Sleep Quality Index at two time points (2006-2008 and 2011-2014).
• Evaluated white matter integrity using MRI: white matter lesion (WML) volume and diffusion tensor imaging for microstructural integrity.

Main Results:

• Baseline sleep complaints were not associated with changes in white matter lesion volume or global white matter microstructure.
• Tract-specific analysis showed a potential link between sleep complaints and integrity of brainstem tracts, but this was not significant after multiple testing correction.
• White matter properties (micro- or macro-structural) were not related to changes in sleep complaints over time.

Conclusions:

• The study provides evidence against sleep complaints causing white matter changes in the aging brain.
• Cerebral white matter pathology does not appear to underlie subjective sleep complaints in older individuals.
• Findings suggest these common aging phenomena are not etiologically linked.