Background The aim of the study was to assess functional changes in microcirculation in primary hypertension and their dependence on blood pressure values.
Materials and methods We enrolled 90 subjects under 50 years of age: 30 healthy persons, 30 patients with newly diagnosed hypertension and 30 - with untreated chronic hypertension, which lasted for at least for 5 years. Rest flow in microcirculation in basal condition and hyperemic reaction after 3 minutes ischaemia at base temperature and at temperature of 44°C were assessed based on laser Doppler flowmetry Periflux 5000 (Perimed, Sweden). Blood pressure measurements were obtained during 24-hour ambulatory monitoring procedure (SpaceLabs 90 207). Studied parameters of microcirculation and age, body mass index, waist to hip ratio, mean 24-hour systolic and diastolic blood pressures were analyzed with aspect of correlation and regression model.
Results Mean and maximal post-occlusive flow at base temperature was higher in hypertensives than normotensive controls. Time to reach maximal post-occlusive flow at temperature of 44°C was significantly elongated in hypertensives than healthy subjects. Values of post-occlusive blood flow parameters were mainly related to blood pressure variability. In multi-factors analysis the age, abdominal obesity, mean systolic and diastolic 24-hour pressures significantly influenced the function of microcirculation. Conclusions Post-ischaemic reaction of skin microcirculation was altered in young hypertensives with longer time needed to get higher values of flow than controls. Flow changes were related to the values and variability of blood pressure.