Differences in rate of functional decline across three dementia types

Area of Science:

• Neuroscience
• Gerontology
• Clinical Neurology

Background:

• Alzheimer's disease (AD), dementia with Lewy bodies (DLB), and vascular dementia (VaD) are common neurodegenerative disorders.
• Understanding differences in functional decline rates is crucial for patient management and prognosis.

Purpose of the Study:

• To estimate and compare the rates of functional decline in AD, DLB, and VaD.
• To investigate if age or sex influences these differences in functional decline.

Main Methods:

• Utilized data from 5848 participants (≥60 years) diagnosed with probable AD, DLB, or VaD from 32 U.S. Alzheimer's Disease Centers.
• Functional Activities Questionnaire (FAQ) scores were analyzed using multiple linear regression with generalized estimating equations over a mean follow-up of 2.0 years.
• Models were adjusted for demographics, comorbidities, symptom duration, and cognitive status.

Main Results:

• Vascular dementia (VaD) patients exhibited a statistically significant slower rate of functional decline compared to Alzheimer's disease (AD) patients (mean annual rate difference: -0.91).
• While VaD patients declined slower than dementia with Lewy bodies (DLB) patients, this difference was not statistically significant.
• No significant differences in the rate of functional decline were observed between DLB and AD patients. Younger participants within each dementia group experienced a more rapid decline.

Conclusions:

• Vascular dementia (VaD) is associated with a slower rate of functional decline compared to Alzheimer's disease (AD).
• No significant differences in functional decline rates were found between dementia with Lewy bodies (DLB) and either AD or VaD.
• These findings can inform clinical expectations regarding the average progression of functional impairment in these three common dementia types.