Searching for surrogate markers of cognitive impairment in small vessel disease: a magnetic resonance imaging and blood biomarker study

• Main Author: Patel, Bhavini
• Published: St George's, University of London 2013
• Subjects: 616.81
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.617005

Cerebral small vessel disease (SVD) is a chronic disease of the small cerebral blood vessels and a common cause of dementia. Surrogate markers for cognitive impairment are required for future treatment trials. Patients with SVD have similar risk factors and MRI features as Alzheimer's disease. Blood biomarkers would be useful for diagnostic and prognostic purposes. St George's Cognition and Neuroimaging Study (SCANS) is a longitudinal study investigating the potential of MRI as a surrogate marker for cognitive impairment. This report examines the baseline data from SCANS. 121 patients with lacunar stroke and white matter hyperintensities had multi modal MRI, neuropsychological testing and had blood sampling for biomarkers of endothelial activation . Patient group performed worse in executive function and information processing speed compared to normative data. Patients had more white matter lesions, smaller whole brain volumes and lower fractional anisotropy and higher mean diffusivity on diffusion tensor imaging. Multiple regression, suggested brain volume was the best predictor of impaired information speed processing (P=0.001) and median white matter FA for executive dysfunction (p=0.004). High numbers (>9) of cerebral microbleeds were associated with impaired executive dysfunction. Blood biomarkers were tested in 106 patients. Patients had lower tissue factor (TF), tissue plasminogen activator (tPA) antigen and plasmin activation inhibitor-1 than controls. TF was associated with lesion volume and tPA was associated with the number of clinical strokes.