Diffusion tensor imaging and cognition in cerebral small vessel disease The RUN DMC study

AbstractBackgroundCerebral small vessel disease (SVD) is very common in elderly and related to cognition, although this relation is weak. This might be because the underlying pathology of white matter lesions (WML) is diverse and cannot be properly appreciated with conventional FLAIR MRI. In addition, conventional MRI is not sensitive to early loss of microstructural integrity of the normal appearing white matter (NAWM), which might be an important factor. Diffusion tensor imaging (DTI) provides alternative information on microstructural white matter integrity and we have used this to investigate the relation between white matter integrity, in both WML and NAWM, and cognition among elderly with cerebral SVD.MethodsThe RUN DMC study is a prospective cohort study among 503 independently living, non-demented elderly with cerebral SVD aged between 50 and 85years. All subjects underwent MRI and DTI scanning. WML were segmented manually. We measured mean diffusivity (MD) and fractional anisotropy (FA), as assessed by DTI in both WML and NAWM.ResultsInverse relations were found between MD in the WML and NAWM and global cognitive function (β=−.11, p<0.05; β=−.18, p<0.001), psychomotor speed (β=−.15, p<0.01; β=−.18, p<0.001), concept shifting (β=−.11, p<0.05; β=−.10, p<0.05) and attention (β=−.12, p<0.05; β=−.15, p