Association of White-Matter Lesions with Brain Atrophy Markers: The Three-City Dijon MRI Study

Abstract

Background: Brain atrophy and white-matter lesions (WML) are common features at cerebral MRI of both normal and demented elderly people. In a population-based study of 1,792 elderly subjects aged 65–80 years, free of dementia, who had a cerebral MRI at entry, we investigated the relationship between WML volume and brain atrophy markers estimated by hippocampal, gray matter (GM) and cerebrospinal fluid (CSF) volumes. Methods: An automated algorithm of detection and quantification of WML was developed, and voxel-based morphometry methods were used to estimate GM, CSF and hippocampal volumes. To evaluate the relation between those volumes and WML load, we used analysis of covariance and multiple linear regression models adjusting for potential confounders and total intracranial volumes. Results: Age was highly correlated with WML load and all brain atrophy markers. Total WML volume was negatively associated with both GM (β = –0.03, p < 0.0001) and hippocampal volumes (β = –0.75, p = 0.0009) and positively with CSF volumes (β = 0.008, p = 0.02) after controlling for sex, age, education level, hypertension and apolipoprotein E genotype. Evidence for a relationship between brain atrophy markers and WML was stronger for periventricular WML. We found that the relationship between WML and hippocampal volumes was independent of other brain tissue volumes. Conclusion: These results suggest that, in the brain of nondemented elderly subjects, degenerative processes and vascular changes co-occur and are related independently of vascular risk factors.