Sleep duration and efficiency are associated with plasma amyloid-β7 in non-demented older people

Study objectives This study aims to investigate the extent to which sleep duration and efficiency are associated with plasma amyloid-beta (A beta) levels in non-demented older people. Methods This study is a cross-sectional analysis of 305 non-demented older people. Sleep duration and efficiency were assessed used the Pittsburgh Sleep Quality Index. Levels of plasma A beta were determined by sandwich enzyme-linked immunosorbent assay technique. Associations between sleep variables and plasma A beta levels were evaluated with multivariable linear regression analysis. Results Compared to those with sleep duration > 7 h, participants with sleep duration < 6 h had a higher plasma A beta(42) level (beta = 0.495, 95% CI 0.077 similar to 0.913, p = 0.021) and A beta(42)/A beta(40) ratio (beta = 0.101, 95% CI 0.058 similar to 0.144, p < 0.001). Compared to those with sleep efficiency >= 85%, participants with lower sleep efficiency (65 similar to 74%, <65%) had a higher level of plasma A beta(42) (<65%: beta = 0.627, 95% CI 0.147 similar to 1.108, p = 0.011) and A beta(42)/A beta(40) ratio (65 similar to 74%: beta = 0.052, 95% CI 0.007 similar to 0.097, p = 0.026; <65%: beta = 0.117, 95% CI 0.067 similar to 0.168, p < 0.001). Conclusions These findings indicated that short sleep duration and low sleep efficiency were associated with a high level of A beta(42). A better comprehending of the link between sleep and plasma A beta levels may lead to effective sleep-based intervention to reduce the risk of Alzheimer's disease.