Correlações entre a estabilidade osmótica da membrana de eritrócitos e índices hematológicos e bioquímicos durante tratamento com estatina

Abstract

This study aimed to analyze the correlations between the osmotic stability of the erythrocyte membrane (OSEM) and hematological and lipid indices in a population of 19 volunteers, at five different moments during eight weeks of statin therapy. The OSEM was derived from a typical osmotic fragility curve and properly expressed by the inverse of its midpoint (1/H50) and the variation in the NaCl concentration necessary to produce full hemolysis, since both these parameters are directly related with the OSEM. The OSEM was positively associated with increase in the blood levels of LDL-C and t-C, with the blood levels of LDL-C being the variable more strongly correlated with the stability parameters. The OSEM was also associated with increased values of RDW, in consequence to the elevation in MCV values caused by high blood levels of LDL-C. The OSEM showed inverse correlations with the RBC count, hematocrit values and blood levels of Hb, in consequence to increase in the blood levels of cholesterol to a point in which the high membrane rigidity make those cells more vulnerable to the mechanical disruption caused by shear stress or by their passage through small diameter capillaries. The OSEM was negatively associated with the blood levels of ALT and AST, probably because this in vitro stability reflects better the behavior of the general membrane cells of the organism than the proper in vivo behavior of the proper erythrocytes. The existence of an association between the OSEM and the prognostic ability of RDW in inflammatory processes can be supported by the positive correlation observed between 1/H50 and the N/L ratio. In summary, the blood levels of LDL-C have large influence on the hematological indices in consequence to changes in the stability of the erythrocyte membrane.