Delta Activity at Sleep Onset and Cognitive Performance in Community-Dwelling Older Adults

Abstract

A commentary on this article appears in this issue on page 725.

Longitudinal association of delta activity at sleep onset with cognitive and affective function in community‐dwelling older adults

“…This study is the first to examine the longitudinal effect of DASO based on nocturnal PSG on cognitive and affective functions. As we previously reported utilizing the same cohort, a notable percentage of participants in our study exhibited DASO (19.6%) at baseline (Kawai et al , ), similar to that observed in a daytime EEG study of community‐dwelling older adults (16%) (Katz and Horowitz, ). With respect to our primary hypothesis, we found no evidence of worsening cognitive or affective performance over time being associated with the DASO.…”

“…Our previously reported investigation of the baseline data found a statistically significant difference in the reading condition of the Stroop test (Kawai et al, 2016), with the presence of DASO associated with better performance on this simple reading task measure that captures speed of processing and vigilance.…”

“…Our previously reported investigation of the baseline data found a statistically significant difference in the reading condition of the Stroop test (Kawai et al , ), with the presence of DASO associated with better performance on this simple reading task measure that captures speed of processing and vigilance. In our longitudinal analyses, we also found that the DASO (+) group exhibited better performance on the Stroop reading condition with an effect size of −0.29 (95% CI −0.53, −0.05).…”

“…One participant was identified as a color blind and did not complete the STRCW, but all their remaining data were included in the analysis. Prior work from our and other groups has consistently found lower performance on measures of delayed recall to be associated with increased age (Blachstein and Vakil, 2016;Kawai et al, 2016). Deficits in the other three cognitive domains are common in older adults and are associated with an increased risk of cognitive decline and onset of dementia (Drag and Bieliauskas, 2010).…”

“…Using a cross‐sectional design, our group recently found no significant associations between DASO and several measures of cognition that included memory and executive function (Kawai et al , ). We concluded that DASO most likely represents normal variation.…”