It has been proposed that elevated blood viscosity contributes to atherothrombotic and thromboembolic processes. We evaluated whether there is increased blood viscosity in systemic lupus erythematosus (SLE) that might contribute to cardiovascular complications and reduced tissue perfusion.
Blood viscosity profiles were evaluated in SLE patients to determine whether rheologic disturbances contribute to the cardiovascular risk profile. Blood viscosity profiles were evaluated in 27 patients with SLE and 46 age- and gender-matched controls. Blood viscosity was measured at 37 degrees C and shear rates of 1 s(-1) and 100 s(-1), then corrected to the average hematocrit of the SLE patients.
Corrected blood viscosity values were higher in SLE patients than in controls at 100 s(-1) (P =.002). Positive correlations were found between the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index for SLE, which quantifies damage to 12 organ systems and fibrinogen (rho =.39; P =.042) and plasma viscosity (rho =.38; P =.049).
Because blood viscosity values correlate with the clinical severity of SLE, blood viscosity may contribute to the cardiovascular complications and reduced tissue perfusion in SLE patients. Semin Arthritis Rheum 31:52-57.
Our data indicate that blood viscosity values at a standard hematocrit are elevated in SLE patients. Further investigations are needed to evaluate whether the increased blood viscosity values in SLE patients contribute to cardiovascular complications and tissue ischemia.