Leukoaraiosis is associated with functional impairment in older patients with Alzheimer's disease but not vascular dementia.

Background: Leukoaraiosis (LA) is a common finding in older persons, and might be associated with reduced cognitive performance, gait abnormalities, and functional impairment. Although LA is more frequent in persons affected by dementia, scant data are available about its clinical consequences in this group of patients. Objective: To study the association between presence of LA and functional performance in basic activities of daily living in a sample of older persons affected by dementia. Design: We conducted a cross-sectional study on 214 patients; 77 affected by late onset Alzheimer's disease (LOAD), and 137 by vascular dementia (VD). Functional status was assessed using Barthel Index (BI). LA was assessed using computed tomography. Results: In LOAD patients, LA (OR: 7.87; 1.26-48.94), and MMSE score (OR: 0.83; 0.71-0.98) were associated with the risk of severe disability, independent of age, gender, diabetes, hypertension, coronary heart disease, left ventricular hypertrophy, atrial fibrillation, and brain atrophy. In VD patients, MMSE score (OR: 0.77; 0.64-0.93), and CHD (OR: 7.41; 1.09-50.21), but not LA (OR: 2.07; 0.45-9.45) were associated with a severe functional impairment after multivariate adjustment. Conclusions: Our study suggests that LA might be associated with a worse functional status in basic activities of daily living in patients affected by LOAD but not VD. LA might act synergistically with cognitive and behavioural disturbances to the onset and progression of disability of these patients.