Impact of loss of independence in basic activities of daily living on caregiver burden in patients with Alzheimer's disease: A retrospective cohort study

Aim: To investigate the association between decline of basic activities of daily living (ADL) in each dimension and change in caregiver burden in patients with mild-to-moderate Alzheimer's disease.

Methods: This retrospective study included 117 outpatients with Alzheimer's disease who presented to the Memory Clinic at the National Center for Geriatrics and Gerontology in Japan between September 2010 and April 2014 (mean age 77.3 ± 6.4 years; 68.6% women). Patients and their caregivers completed comprehensive geriatric assessment at baseline and at the 3-year follow up. Caregiver burden was assessed using the Japanese version of the Zarit Burden Interview. ADL were assessed by the Barthel Index. Among patients with full points on each subitem of the Barthel Index at baseline, incident ADL decline was defined as a loss of at least 5 points at the 3-year follow up. Other confounding factors including demographic data, cognitive function, vitality, and behavioral and psychiatric symptoms of dementia were also assessed. The longitudinal relationship between incident ADL decline and changes in caregiver burden was evaluated by multivariate linear regression, adjusted for confounding variables.

Results: In descending order, declines in ADL at 3 years were noted in bathing (25.4%), bowel control (25.4%), grooming (22.9%) and bladder control (22.9%). On multivariate analyses, ADL declines in feeding (b = 17.2, P < 0.01) and bathing (b = 11.0, P = 0.02) were significantly associated with increased caregiver burden.

Conclusion: Incident ADL declines in feeding and bathing are significant risk factors for increased caregiver burden in patients with Alzheimer's disease. Geriatr Gerontol Int 2019; 19: 1243-1247.