Erythrocyte rigidity in healthy patients and patients with cardiovascular disease risk factors

The normal values for erythrocyte rigidity as measured by the "Selective Erythrocyte Rigidometer" were derived from a group of 275 apparently healthy subjects without risk factors. These individuals were randomly selected from an address book. The normal values ranged from 0.83-1.19 (median: 1.01). Quality control was conducted throughout the study and the analytical reliability was verified (day-to-day coefficient of variation VCd was 7.5%; coefficient of variation in series VCs was 3.1%). Inter- and intraindividual fluctuations in erythrocyte rigidity in the 8.3% and 6.1% ranges respectively were found in 20 apparently healthy subjects in the course of a 6-month study. No relationship was found between either age or sex and erythrocyte rigidity. Significantly higher erythrocyte rigidity values were found in patients with risk factors however; this applies to hypertensive patients, patients with diabetes mellitus, but also to apparently healthy subjects who were either overweight or smokers. Patients with disordered lipometabolisms on the other hand did not show any change in erythrocyte deformability when compared with healthy subjects.