Factor Structure of the Geriatric Depression Scale and Relationships with Cognition and Function in Alzheimer's Disease

Background/Aims: No study to date has systematically explored whether the Geriatric Depression Scale (GDS) measures symptoms of apathy and dysphoria in patients with Alzheimer's disease (AD) or related these constructs to cognitive and functional status. Methods: Exploratory factor analysis (EFA) was used to identify factors of the GDS in a sample of 569 patients with probable AD. Two-way ANOVAs were used to determine the relationship of apathy and dysphoria to neuropsychological and functional measures. Results: The EFA yielded four factors associated with apathy, dysphoria, social withdrawal and cognitive impairment. Apathy was associated with greater impairments in verbal memory, motor speed, and functional abilities. Conclusion: Apathy, but not dysphoria, was associated with some cognitive and functional variables. Results suggest that the GDS may be used as a screening measure for symptoms of apathy in AD. Copyright (C) 2012 S. Karger AG, Basel