Polysomnographic and Clinical Correlates of Behaviorally Observed Daytime Sleep in Nursing Home Residents

Abstract

The causes of daytime sleepiness among nursing home residents have not been well recognized. This study examines clinical and polysomnographic factors that are associated with daytime sleepiness among nursing home residents. One hundred seventy-four nursing home residents from eight nursing homes in Atlanta, Georgia, participated in the study. Demographic and clinical data were obtained from medical records and assessment of participants obtained by trained research staff. Daytime sleepiness was determined by behavioral sleep-wake observation performed every 15 minutes. Overnight polysomnography was performed in a subgroup of the sample. The mean +/- standard deviation age was 83.4 +/- 8.8 years, and 136 participants were women (78%). The mean percentage +/- standard deviation of behavioral observations with sleep (BOS%) was 19.5 +/- 13.3%. Participants who were able to ambulate independently had significantly lower BOS% (14.2 +/- 9.6 vs 21.2 +/- 6.0, p =.001). Mini-Mental State Examination score was negatively correlated with BOS% (rho = -.279, p =.001). Among 48 participants who had polysomnography, sleep latency, total sleep time, wake after sleep onset, and sleep efficiency were not associated with BOS%. There was a significant negative correlation between BOS% and percentage of time spent in rapid eye movement sleep (rho = -.367, p =.010). Linear regression analyses, with BOS% as the dependent variable, showed that percentage of time spent in rapid eye movement sleep was the only variable independently predicting BOS%. Absence of association between BOS% and nocturnal sleep suggests that the causes of daytime sleepiness and nocturnal sleep problems may not be related. This finding may have important implications for interventions that aim to reduce daytime sleepiness among nursing home residents.