Baseline excessive daytime sleepiness (EDS) was associated with increased longitudinal β-amyloid (Aβ) accumulation in elderly persons without dementia, according to a recent study, suggesting that those with EDS may be more vulnerable to pathologic changes associated with Alzheimer disease (AD). This prospective analysis included participants enrolled in the Mayo Clinic Study of Aging, a longitudinal population-based study in Olmsted County, Minnesota. Of 2,900 participants, 2,172 (74.9%) agreed to undergo carbon 11–labeled Pittsburgh compound B positron emission tomography (PiB-PET). Researchers included 283 participants aged ≥70 years without dementia who completed surveys assessing sleepiness at baseline and had at least 2 consecutive PiB-PET scans from January 1, 2009, through July 31, 2016, after excluding 45 (13.7%) who had a comorbid neurologic disorder. They found:

• 63 participants (22.3%) had EDS.
• Baseline EDS was significantly associated with increased regional Aβ accumulation in the anterior cingulate, posterior cingulate-precuneus, and parietal regions.
• Association of EDS with longitudinal Aβ accumulation was stronger in participants with baseline global PiB positivity in the anterior cingulate and cingulate-precuneus regions.