Rheological Variations among Nigerians with Different Hemoglobin Genotypes

Abstract

A total of one hundred and Forty-five (145) subjects comprising of 50 homozygous Hemoglobin A subjects (HbAA), 50 heterozygous hemoglobin AS (HbAS) subjects and 45 homozygous hemoglobin S (HbSS) subjects were recruited for this study with a view to ascertain variations in the Hemorheological values possibly associated with the inherited hemoglobin genotype. Some Hemorheological determinants such as whole blood viscosity (WBV) and plasma viscosity (PV) and Plasma Fibrinogen Concentration (PFC) were measured with standard methods. We recorded a relatively unchanged whole blood viscosities in subjects with various hemoglobin genotypes (AA, AS and SS; P>0.05, respectively). Also, there were no significant differences in PV values of HbAA and HbAS while there were significant increases in PV and PFC of HbSS compared with others (P<0.05, respectively). However, relative erythrocyte viscosity (REV) of HbSS became significantly reduced when repeated with saline after replacing plasma with saline (P<0.05, respectively), to ascertain the erythrocytic cellular viscosity. We conclude that increased plasma viscosity coupled with that of PFC in HBSS could be due to plasmatic components and that cellular rheologic properties of the erythrocytes may be dependent on its content of hemoglobin while whole blood viscosities are stable in native blood irrespective of haemoglobin genotypes.

Keywords: Hemorheology, Plasma Viscosity, erythrocyte cellular viscosity, hemoglobin genotype