Cerebral white matter lesions and cognitive function: The Rotterdam scan study

TLDR

Cerebral white matter lesions are linked to cognitive dysfunction, but it is unclear whether periventricular versus subcortical lesions differentially affect specific cognitive domains such as memory or psychomotor speed. The study examined the relationship between periventricular and subcortical WMLs and cognitive functioning in 1,077 elderly subjects. WMLs were quantified using an extensive rating scale on 1.5‑T MRI scans, and cognitive function was measured with multiple neuropsychological tests to produce composite scores for psychomotor speed, memory, and global cognition. Both periventricular and subcortical lesions were initially linked to all cognitive measures, but after adjusting for each other only periventricular lesions remained associated with global cognition; severe periventricular lesions were linked to nearly a one‑standard‑deviation deficit in psychomotor speed and more than half a standard deviation in global cognition, indicating that speed‑related tasks are more affected than memory tasks. Ann Neurol 2000;47:145–151.

Abstract

Cerebral white matter lesions (WMLs) have been associated with cognitive dysfunction. Whether periventricular or subcortical WMLs relate differently to cognitive function is still uncertain. In addition, it is unclear whether WMLs are related to specific cognitive domains such as memory or psychomotor speed. We examined the relationship between periventricular and subcortical WMLs and cognitive functioning in 1,077 elderly subjects randomly sampled from the general population. Quantification of WMLs was assessed by means of an extensive rating scale on 1.5-T magnetic resonance imaging scans. Cognitive function was assessed by using multiple neuropsychological tests from which we constructed compound scores for psychomotor speed, memory performance, and global cognitive function. When analyzed separately, both periventricular and subcortical WMLs were related to all neuropsychological measures. When periventricular WMLs were analyzed conditional on subcortical WMLs and vice versa, the relationship between periventricular WMLs and global cognitive function remained unaltered whereas the relationship with subcortical WMLs disappeared. Subjects with most severe periventricular WMLs performed nearly 1 SD below average on tasks involving psychomotor speed, and more than 0.5 SD below average for global cognitive function. Tasks that involve speed of cognitive processes appear to be more affected by WMLs than memory tasks. Ann Neurol 2000;47:145–151.