Total cerebral small vessel disease score and cognitive performance in community-dwelling older adults. Results from the Atahualpa Project

Objective: Cerebral small vessel disease (SVD) is inversely associated with cognitive performance. However, whether the total SVD score is a better predictor of poor cognitive performance than individual signatures of SVD is inconclusive. We aimed to estimate the combined and independent predictive power of these MRI findings. Methods: Atahualpa residents aged ≥60 years underwent brain MRI. Cognitive performance was measured by the Montreal Cognitive Assessment (MoCA). The presence of moderate-to-severe white matter hyperintensities, deep cerebral microbleeds, lacunar infarcts, and >10 enlarged perivascular spaces was added for estimating the total SVD score ranging from 0 to 4 points. Montreal Cognitive Assessment predictive models were fitted to assess how well the total SVD score or each of its components predicts cognitive performance. Results: Of 351 eligible candidates, 331 (94%) were included. The total SVD score was 0 points in 202 individuals (61%), 1 point in 67 (20%), 2 points in 40 (12%), 3 points in 15 (5%), and 4 points in seven (2%). A generalized lineal model showed an inverse relationship between the total SVD score and the MoCA (p = 0.015). The proportion of variance in the MoCA score explained by the SVD score was 32.8% (R² = 0.328). This predictive power was similar for white matter hyperintensities (R² = 0.306), microbleeds (R² = 0.313), lacunar infarcts (R² = 0.323), and perivascular spaces (R² = 0.313). Conclusions: This study shows a significant association between the SVD score and worse cognitive performance. The SVD score is a predictor of poor cognitive performance. This predictive power is not better than that of isolated neuroimaging signatures of SVD.