Sleep Disturbances in Patients with Alzheimer’s Disease: A Cross-Sectional Study in Nursing Home and Community-Dwelling Older Adults

Background Sleep disturbances are among the most common non-cognitive symptoms of Alzheimer’s disease (AD) and may substantially affect disease progression, patient functioning, and caregiver burden. Emerging evidence suggests that sleep disorders may appear in the early stages of neurodegeneration and may even precede the clinical diagnosis of dementia. However, limited research has compared sleep disturbances between patients with AD living in institutional care and those living in community settings. Methods This cross-sectional study included 70 patients diagnosed with Alzheimer’s disease. Participants were recruited from two nursing homes and from individuals living at home who attended occupational therapy at a community support center for patients with AD. Sleep disturbances were assessed using a questionnaire developed for the purposes of this study as well as standardized instruments, including the Epworth Sleepiness Scale (ESS) and the Athens Insomnia Scale (AIS). Cognitive functioning was evaluated using the Blessed Dementia Scale and the Clock Drawing Test. Statistical analyses were performed using non-parametric methods, including the Mann–Whitney U test, Kruskal–Wallis test, and Spearman’s rank correlation coefficient. Results Sleep disturbances were highly prevalent among the studied patients. The most frequently reported symptoms included excessive daytime sleepiness, frequent nocturnal awakenings, difficulty initiating sleep, and snoring. Many participants reported experiencing sleep disturbances prior to the clinical diagnosis of Alzheimer’s disease. A significant positive correlation was observed between the duration of Alzheimer’s disease and the severity of sleep disturbances. In addition, residence in nursing institutions was associated with a higher prevalence of sleep disturbances compared with community-dwelling patients. Frequent daytime naps were also associated with increased severity of sleep-related problems. Conclusions Sleep disturbances are highly prevalent in patients with Alzheimer’s disease and may occur even before the clinical diagnosis of dementia. Both environmental factors and disease duration appear to influence the severity of sleep problems. Early recognition and management of sleep disturbances may represent an important component of comprehensive care and may contribute to improving the quality of life of patients with Alzheimer’s disease.