Subcortical vascular disease and functional decline: a 6-year predictor study.

OBJECTIVES: To identify predictors of activity of daily living (ADL) and instrumental activity of daily living (IADL) decline in a population with subcortical vascular dementia (SVD) and to evaluate potential mechanism of decline. DESIGN: Longitudinal. SETTING: Hospital-based. PARTICIPANTS: Computed tomographic (CT) scanning identified 77 participants as having subcortical infarction. MEASUREMENTS: Participants were neurologically, neuropsychologically, behaviorally, and functionally assessed four times over 5.82 years. Baseline data were grouped into four modules: basic demographic and risk factor, CT scan, neurological and other clinical, and neuropsychological and behavioral. Multivariate analysis determined predictors of decline in ADLs and IADLs. RESULTS: Predictors of ADL decline were age, alcohol consumption, coordination, snout reflex, and performance on a neuropsychological test (Block Design). Predictors of IADL decline were predominantly cognitive and included the presence of paratonia and performance on the two neuropsychological tests (attention and memory tasks). CONCLUSIONS: These findings suggest that cognitive impairments are most likely to have an effect on IADL function, because the skills involved are complex and involve integrative activity, whereas physical and cognitive impairments combined are likely to compromise ADL function, given the more basic and physical nature of the functions involved. These findings indicate that in people with SVD, both ADL and IADL status should be monitored, because, for many, decline in function over time is likely, and thus the provision of appropriate support required.