Hemostatic Biomarkers Succeed While Inflammatory Biomarkers Fail To Differentiate Vascular Dementia From Alzheimer'S Disease

Introduction: A reliable plasma biomarker in differentiating between Alzheimer’s disease (AD) and Vascular dementia (VaD) is the need of the hour, in most memory clinics. Hypothesis: We assessed the hypothesis that plasma inflammatory [Interleukin 6 (IL 6) and C-Reactive Protein (CRP)] and hemostatic (Fibrinogen and D dimer) biomarkers can aid in differentiating between AD and VaD. Methods: Neuropsychological assessment, MRI brain, FDG-PET brain and CSF biomarkers of AD (Aβ42 and total tau) were used for establishing the diagnosis of Mild Cognitive Impairment (MCI), AD or VaD. ELISA analyses for IL6, Fibrinogen, D dimer and CRP were performed according to the manufacturers’ protocols. Results: During the study period (January 2013-April 2014), 68 diagnosed patients of AD/MCI/VaD were included. FDG PET brain, plasma fibrinogen, D dimer, IL6 and CRP were done in all 68 patients while 48 patients underwent CSF biomarker analysis. Sixteen patients had MCI, of which 11 were MCI-AD and 5 were MCI-VaSC. There were 41 patients with AD (Mild AD- 9, Mod AD -23, Severe AD- 9) and 11 patients with VaD. The Alzheimer group (MCI-AD and AD) and Vascular group (MCI VaSC u0026 VaD) consisted of 52 and 16 patients respectively. Table 1 depicts biomarker levels. Alzheimer and Vascular groups did not exhibit significant difference in IL6 and CRP levels. Plasma fibrinogen levels were significantly higher in VaD and vascular group as compared to Alzheimer group. But MCI-VaSC was not significantly different from MCI-AD. Plasma D dimer levels were significantly higher in all vascular subgroups compared to Alzheimer subgroups except between MCI-VaSC and MCI-AD. Conclusion: In conclusion, hemostatic biomarkers (Plasma Fibrinogen and D dimer) succeed, whereas inflammatory biomarkers (IL6 and CRP) fail in differentiating VaD from AD.