AbstractBackground: Blood viscosity has a role in modulating cardiovascular homeostasis; changes in this parameter have been associated with cardiovascular mortality and morbidity. However, it remains unclear whether these changes are (1) involved in the pathophysiology of disease, (2) an epiphenomenon, or (3) the expression of counterregulatory mechanisms. We report data on the normal values of blood viscosity and its association with cardiovascular risk factors, prevalent cardiovascular disease, and blood pressure in a large population-based cohort study.
Methods and results: Viscosity was calculated using validated formulae and its associations were explored in 15,010 participants (mean 55.0, min–max: 35–74 years old; 49.5% women) from the Gutenberg Health Study as well as in a subgroup of 3223 subjects (61.1% women, mean age 49.2, min–max 35–74 years old) without risk factors or self-reported cardiovascular disease. Age- and gender-adjusted mean values for viscosity were defined. Regression models showed a relationship between classical risk factors and blood viscosity measures; the overall R 2 of the multiple linear regression model was however as low as 0.067 and 0.049 for high and low shear stress viscosity, respectively. After correction for cardiovascular risk factors, there was a very mild association between viscosity and prevalent coronary artery disease and heart failure. Systolic, mean and diastolic blood pressure increased with increasing blood viscosity after correction for age and gender.
Conclusions: We provide reference values for viscosity in a population-based cohort. Blood viscosity decreases in older subjects and shows a very mild association with cardiovascular risk factors and prevalent disease in our cohort. There is a linear positive association between viscosity and blood pressure.