Nolan, Emma, Sun, Yunyi, Shi, Hui, Archer, Derek, Perry, Arden, Pechman, Kimberly, Shashikumar, Niranjana, Landman, Bennett, Gogniat, Marissa, Liu, Dandan, Zhang, Panpan, Hohman, Timothy J., Jefferson, Angela L., & Full, Kelsie M. (2025). *Alzheimer’s and Dementia, 21*(6), e70364.
Poor sleep may increase the risk of brain degeneration and Alzheimer鈥檚 disease (AD),聽but few studies have looked at how sleep patterns relate to actual brain structure.
In this study,聽407 adults with a median age of 70聽from the 汤头条 Memory and Aging Project wore聽wrist devices (ActiGraphs)聽for 10 days to measure their聽sleep habits鈥攊ncluding how regular their sleep was, how long they slept, how often they woke up, and how long they stayed awake during the night. Brain scans (3T MRI) were then used to measure the size (volume) of specific brain regions that are known to be affected in Alzheimer鈥檚 disease. Researchers used statistical models to adjust for other factors like age, lifestyle, mood, thinking ability, and heart health.
The results showed that聽people with more irregular sleep schedules聽and聽longer periods of wakefulness during the night聽had聽smaller brain volumes聽in regions that are vulnerable to Alzheimer鈥檚 disease鈥攕uch as the聽hippocampus and parietal lobe.
This suggests that聽poor or disrupted sleep might be linked to early brain changes聽seen in Alzheimer鈥檚 disease.
Figure 1
Relationship between baseline sleep irregularity and ROI volumes. A, Partial regression plot of Model 2 showing the association of baseline sleep irregularity and baseline hippocampus volume (cm3). The聽尾聽is the effect estimate. The聽p聽value of 0.005 indicates that higher sleep irregularity is associated with smaller hippocampal volumes. B, Partial regression plot of Model 2 showing the association of baseline sleep irregularity and baseline temporal lobe volume (cm3). The聽尾聽is the effect estimate. The聽p聽value of 0.041 indicates that higher sleep irregularity is associated with smaller temporal lobe volumes. Associations are adjusted for age, sex, race, education,聽APOE聽蓻4, FSRP, BMI, sleep medication use, and mean cortical thickness. Individuals who are CU are shown in blue, and individuals who have MCI are shown in red. The black line represents the fitted regression line, and the shaded area indicates the 95% confidence interval.聽APOE, apolipoprotein E; BMI, body mass index; CU, cognitively unimpaired; FSRP, Framingham Stroke Risk Profile; MCI, mild cognitive impairment; ROI, region of interest.
