Study suggests possible marker of Alzheimer’s disease associated with worse sleep quality


Yo-El S Ju, Washington University School of Medicine, St Louis, and colleagues suggested in a study published online first in JAMA Neurology, that amyloid deposition in the preclinical stage of Alzheimer’s disease appears to be associated with worse sleep quality but not with changes in sleep quantity.

The cross-sectional study from October 2010 to June 2012 recruited cognitively normal individuals (n=145) 45 years of age or older and actigraphy data to measure sleep were recorded for 142 participants. Sleep was measured for two weeks and cerebrospinal fluid B-amyloid42 levels were used to determine whether amyloid deposition was present or not. Amyloid deposition was present in 32 participants (22.5%), according to the study results.

“This group had worse sleep quality, as measured by sleep efficiency (80.4% vs. 83.7%) compared with those without amyloid deposition […] in contrast, quantity of sleep was not significantly different between groups, as measured by total sleep time,” said the authors.

Frequent napping, three or more days per week, also was associated with amyloid deposition (31.2% vs. 14.7%), according to the study results.