Insomnia and daytime sleepiness in people with dementia residing in assisted living: findings from the Maryland Assisted Living Study

Objective To estimate the frequency and correlates of insomnia and daytime sleepiness among people with dementia in AL facilities. Methods Participants were randomly selected from 22 different assisted living facilities in Maryland. A total of 124 dementia participants were included in the analysis. All participants were rated on an 11-item sleep questionnaire regarding insomnia and daytime sleepiness. Results Sleep disturbance was present in 59.2% of people with dementia. Of the total sample, 21.8% had insomnia only (IN); 21.6% had excessive daytime sleepiness only (DS); and 16.8% had both IN and DS. 40.8% had no sleep disturbance. IN and DS scores were not significantly associated with each other (r=0.07, p=0.43). Of those in the IN group, the majority had mild and moderate dementia and of those in the DS only group the majority had severe dementia. Those with IN only performed the best and DS only performed the worst on both cognitive measures (the Mini Mental State Examination) (F=3.26, p=0.014), and on physical measures (the physical subscale of the psychogeraitric dependency rating scale) (F=6.09, p < 0.001). There was no significant difference between the groups on the Cornell scale for depression in dementia. Conclusion The frequency of insomnia and daytime sleepiness in dementia subjects in AL is similar to that found in nursing homes. Daytime sleepiness is associated with poorer cognitive and day-to-day functioning. Effective management of DS may lead to improved functioning in the AL residents. Insomnia is associated with the best outcomes, even better than those with no sleep disturbance. This finding needs to be replicated. Copyright (c) 2007 John Wiley & Sons, Ltd.