Risk of decline in functional activities in dementia with Lewy bodies and Alzheimer disease.

We examined the risk of 1-year decline in 4 everyday activities in patients with dementia with Lewy bodies (DLB), relative to patients with Alzheimer disease (AD). Data were from the National Alzheimer's Coordinating Center, gathered from 32 Alzheimer's Disease Centers. Participants (n=1880) were: aged 60+ years, demented with a primary clinical diagnosis of probable AD or DLB, and had a global Clinical Dementia Rating of 0.5 to 2. The activities were measured with the Functional Activities Questionnaire. In modified Poisson regression models adjusted for demographics, baseline activity, years from symptom onset, cognitive impairment, and comorbidities; DLB participants aged 67 to 81 years had 1.5 to 2 times increased risk of decline in performing basic kitchen tasks, engaging in games/hobbies, and paying attention/understanding, relative to AD participants of the same age (P<0.05). There was no significant difference between AD and DLB participants beyond this age range. For decline in ability to go shopping alone, there was also no significant difference between AD and DLB participants. In summary, the functional course of DLB, relative to AD, may depend on the age of the patient. These findings may provide anticipatory guidance to families and healthcare providers, which may be useful in the planning of care strategies.