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Updated: May 20, 2026
08:43
Application of Granger Causality Analysis of the Directed Functional Connection in Alzheimer's Disease and Mild Cognitive Impairment
Published on: August 7, 2017
Delusions increase functional impairment in Alzheimer's disease
Corinne E Fischer1, Zahinoor Ismail, Tom A Schweizer
1Mental Health Service, St. Michael's Hospital, Toronto, Ont., Canada. FISCHERC@smh.ca
Dementia and Geriatric Cognitive Disorders
|July 21, 2012
Summary
Alzheimer's disease patients with delusions experience greater functional impairment. This study highlights the impact of delusions on daily living activities in Alzheimer's disease patients.
Area of Science:
- Neuroscience
- Gerontology
- Psychiatry
Background:
- Delusions are a common symptom in Alzheimer's disease (AD).
- Previous research suggests a link between delusions and functional impairment in AD.
- Existing studies may underestimate the impact due to a lack of sensitive functional assessment tools, particularly for executive functions.
Purpose of the Study:
- To investigate the association between delusions and functional impairment in Alzheimer's disease.
- To utilize functional instruments sensitive to changes in frontal executive function.
- To provide a more accurate assessment of the impact of delusions on functional status in AD.
Main Methods:
- A comparative study involving Alzheimer's disease patients with and without delusions.
- Cognitive tests and questionnaires assessing depression and quality of life were administered to patients.
- Caregiver-reported questionnaires assessed functional impairment, caregiver burden, and behavioral symptoms.
Main Results:
- Alzheimer's disease patients with delusions (n=19) showed significantly greater functional impairment compared to those without delusions (n=19).
- This difference was measured using the Disability Assessment for Dementia Scale.
- Patients were matched for age, education, and global cognitive function to ensure comparability.
Conclusions:
- Delusions in Alzheimer's disease are associated with significantly worse functional performance.
- The findings underscore the importance of addressing delusions to improve functional outcomes in AD patients.
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