Cognitive Function in Small Vessel Disease: The Additional Value of Diffusion Tensor Imaging to Conventional Magnetic Resonance Imaging: The RUN DMC Study

Issue title: Physiopathology of Vascular Risk Factors in Alzheimer's Disease

Guest editors: Jack de la Torre

Article type: Research Article

Authors: van Norden, Anouk G.W.^{; 1} | van Uden, Inge W.M.^{; 1} | de Laat, Karlijn F. | van Dijk, Ewoud J. | de Leeuw, Frank-Erik^{; *}

Affiliations: Donders Institute for Brain, Cognition and Behavior, Centre for Neuroscience, Department of Neurology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands

Correspondence: [*] Correspondence to: F.-E. de Leeuw, MD, PhD, Donders Institute for Brain, Cognition and Behaviour, Centre for Neuroscience, Department of Neurology, Radboud University Nijmegen Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands. Tel.: +31 243613396; Fax: +31 243541122; E-mail: H.deLeeuw@neuro.umcn.nl.

Note: [1] Both authors contributed equally to this study.

Abstract: The structural integrity of the cerebral white matter, including that of the white matter lesions (WML) and of the surrounding normal appearing white matter (NAWM), can be assessed with diffusion tensor imaging (DTI), which is suggested to be of added value in the explanation of cognitive dysfunction in cerebral small vessel disease (SVD). We investigated the value of DTI of NAWM and WML in addition to conventional magnetic resonance imaging (MRI) parameters in the variance of cognitive performance in subjects with SVD. 499 individuals with SVD, 50–85 years, without dementia, underwent MRI scanning, including a DTI sequence. Grey matter, white matter (WM), and WML volume, number of microbleeds, lacunar and territorial infracts, and mean diffusivity (MD) and fractional anisotropy (FA) in NAWM, WML, and total WM were related to cognitive performance in multivariate regression analyses, after adjustment for age, gender, and education. All MRI parameters together accounted for 1–6% of the variance in cognitive function on top of 22–36% already explained by age, gender, and level of education. Both mean MD and FA of the NAWM, WML, and total WM did not substantially contribute to the explained variance of cognitive function, to that already explained by conventional MRI parameters. When considered separately, the MD of the (NA)WM had the strongest association with cognitive performance. In conclusion, DTI of NAWM and WML has limited additional value to conventional MRI parameters in the etiological explanation of the variance in cognitive function among individuals with SVD.

Keywords: Aging, cerebral small vessel disease, cognition, diffusion tensor imaging, imaging, lacunar infarcts, magnetic resonance imaging, microbleeds, white matter lesions

DOI: 10.3233/JAD-2012-120784

Journal: Journal of Alzheimer's Disease, vol. 32, no. 3, pp. 667-676, 2012