Hemorheolocical and photoplethysmographical modifications with aging

Summary The association of hemorheological patterns with the common risk factors for atherosclerosis is widely known. There are only few data about hemorheological modifications with aging. The objective of our study was to evaluate the relationships of blood and plasma viscosity, the whole blood and red cell filterability, and the amplitude of photoplethysmographical wave to aging and to some risk factors for atherosclerosis. The study involved 278 healthy women, mean age 55.3 ± 11.9 (SD) years. Blood viscosity was positively correlated to body mass index (BMI), total cholesterol/HDL ratio, triglyceridemia, glycemia and hematocrit. Plasma viscosity was positively correlated to age, systolic blood pressure, glycemia, and fibrinogen contents. Whole blood filterability was negatively correlated to diastolic blood pressure, triglyceridemia, glycemia, hematocrit, and fibrinogen contents. Red cell filterability was negatively correlated to age, hematocrit, and fibrinogen. The amplitude of photoplethysmographical wave is inversely correlated to age and systolic blood pressure. Our findings show an increase of plasma viscosity, a decrease of red cell filterability and of the amplitude of photoplethysmographical wave with advancing age. These modifications may contribute to the microcirculatory troubles often evident in aging individuals.