Affiliations: Department of Pathology and Laboratory Medicine, University of California Davis School of Medicine, Sacramento, CA, USA | Shiley Center, Scripps Clinic, La Jolla, CA, USA | Department of Public Health Sciences, Division of Biostatistics, University of California Davis School of Medicine, Sacramento, CA, USA
Note: [] Corresponding author: Dr. Anthony Tze-Wai Cheung, University of California Davis School of Medicine, Department of Pathology and Laboratory Medicine, UC Davis Health Systems Campus, Research III Building, Suite 3400, 4645 Second Avenue, Sacramento, CA 95817, USA. Tel.: +1 916 734 3855; E-mail: [email protected].
Abstract: We hypothesized that abnormalities in hemorheologic parameters, including vessel diameter, flow velocity, and whole blood viscosity (WBV), would be present in Alzheimer's Disease (AD) and would correlate with microvascular abnormalities (vasculopathy). Using the Rheolog™, we obtained WBV profiles, measured at shear rates of 1–1,000 s−1, for 10 AD subjects and age matched non-AD controls. Vessel diameter, flow velocity, and microvascular abnormalities were quantified using computer-assisted intravital microscopy (CAIM) of the conjunctival microcirculation. A Severity Index (SI), scale 0–15, was computed to reflect degree/severity of vasculopathy. AD subjects compared to controls had significantly higher WBV (3.96±0.29 cP vs. 3.34±0.05 cP, sheared at 300 s−1; P<0.05) and SI (7.00±2.36 vs. 0.30±0.70; P<0.05). WBV was correlated (ρs=0.648; P<0.05) with SI in AD subjects. These results strongly suggest the simultaneous involvement of hemorheologic abnormalities and systemic vasculopathy in AD.
