Prevalence of cerebral white matter lesions in elderly people: a population based magnetic resonance imaging study. The Rotterdam Scan Study

Objective-White matter lesions are often seen on MR scans of elderly nondem ented and demented people. They are attributed to degenerative changes of s mall vessels and are implicated in the pathogenesis of cognitive decline an d dementia. There is evidence that especially periventricular white matter lesions are related to cognitive decline, whereas subcortical white matter lesions may be related to late onset depression. The frequency distribution of subcortical and periventricular white matter lesions according to age a nd sex reported. Methods-A total of 1077 subjects aged between 60-90 years were randomly sam pled from the general population. All subjects underwent 1.5T MR scanning; white matter lesions were rated separately for the subcortical region and t he periventricular region. Results-Of all subjects 8% were completely free of subcortical white matter lesions, 20% had no periventricular white matter lesions, and 5% had no wh ite matter lesions in either of these locations. The proportion with white matter lesions increased with age, similarly for men and women. Women tende d to have more subcortical white matter lesions than men (total volume 1.45 ml v 1.29 ml; p=0.33), mainly caused by marked differences in the frontal white matter lesion volume (0.89 ml v 0.70 ml; p=0.08). Periventricular whi te matter lesions were also more frequent among women than men (mean grade 2.5 v 2.3; p=0.07). Also severe degrees of subcortical white matter lesions were more common in women than in men (OR 1.1; 95% confidence interval (95 % CI) 0.8-1.5) and periventricular white matter lesions (OR 1.2; 95% CI 0.9 -1.7), albeit that none of these findings were statistically significant. Conclusions-The prevalence and the degree of cerebral white matter lesions increased with age. Women tended to have a higher degree of white matter le sions than men. This may underlie the finding of a higher incidence of deme ntia in women than in men, particularly at later age.