Anxiety and nighttime behavioral disturbances. Awakenings in patients with Alzheimer's disease.

This study was conducted to describe the relationship between anxiety and nighttime behavioral disturbance in a community-dwelling sample of patients with Alzheimer's disease (AD). Data from 153 patients with probable or possible AD and their family caregivers were analyzed using logistic regression modeling. Ratings of nighttime behavioral disturbance were based on caregiver reports of how often patients had awakened them at night during the past week. Standardized ratings for patient cognitive, functional, and behavioral status, and for caregiver sleep, depression, and burden were collected. Fifty-six percent of the patients with AD showed symptoms of anxiety, and 29% had awakened their caregiver at least once at night during the past week. Patient awakening was associated with higher levels of patient anxiety (odds ratio [OR] = 2.1; confidence Interval [CI] = 1.4, 2.9) and patient impairments in activities of daily living (OR = 1.6, CI = 1.2, 2.3). No other demographic, cognitive, functional, or behavioral variables were significant, including depression. In univariate analyses, individual patient anxiety symptoms (e.g., feeling anxious; showing physical signs of anxiety, agitation, and irritability) were significant risk factors for patient awakenings. Of these, showing physical signs of anxiety remained a significant risk factor in multivariate analyses. Results suggest that anxiety and nighttime awakening are highly interrelated in patients with moderate dementia due to AD, and treatments targeting both may be more efficacious than those focusing on anxiety or sleep alone. They also reveal the importance of assessing anxiety as well as depression in the research and clinical care of patients with AD.