Excessive daytime sleepiness (EDS) and fatigue were associated with cortical thickness reduction in the brain, primarily in regions with increased age-susceptibility, which may indicate accelerated brain aging, a recent study found. Researchers performed a cross-sectional observational study of 1,374 cognitively-normal subjects aged ≥50 years who had a structural MRI. Regional cortical thickness and hippocampal volume were measured. They found:

• 208 participants had EDS, 27 had significant fatigue, and 11 had both.
• Participants with EDS or fatigue had significantly lower cognitive scores, more disturbed sleep, and medical comorbidities.
• The presence of EDS was associated with both global and regional atrophy, whereas fatigue was more associated with frontal and temporal changes.
• Cortical thinning predicted by EDS and fatigue was maximal in the temporal region with average reduction of 34.2 μm and 90.2 μm, respectively.
• Temporal cortical thinning predicted by presence of EDS and fatigue was equivalent to more than 3.5 and 9 additional years of aging, respectively.