Effect of Age on Blood Rheology in Sickle Cell Anaemia and Sickle Cell Haemoglobin C Disease: A Cross-Sectional Study

Abstract

ObjectivesBlood rheology plays a key role in the pathophysiology of sickle cell anaemia (SS) and sickle cell haemoglobin C disease (SC), but its evolution over the lifespan is unknown.Materials and MethodsBlood viscosity, red blood cell (RBC) deformability and aggregation, foetal haemoglobin (HbF) and haematocrit were measured in 114 healthy individuals (AA), 267 SS (161 children + 106 adults) and 138 SC (74 children + 64 adults) patients.ResultsOur results showed that 1) RBC deformability is at its maximal value during the early years of life in SS and SC populations, mainly because HbF level is also at its peak, 2) during childhood and adulthood, hydroxycarbamide treatment, HbF level and gender modulated RBC deformability in SS patients, independently of age, 3) blood viscosity is higher in older SS and SC patients compared to younger ones and 4) haematocrit decreases as SS patients age.ConclusionThe hemorheological changes detected in older patients could play a role in the progressive development of several chronic disorders in sickle cell disease, whose prevalence increases with age. Retarding these age-related haemorheological impairments, by using suitable drugs, may minimize the risks of vaso-occlusive events and chronic disorders.

One-Fifth of Children with Sickle Cell Anemia Show Exercise-Induced Hemoglobin Desaturation: Rate of Perceived Exertion and Role of Blood Rheology

“…Blood rheology is altered in SCA, with patients having a reduction in RBC deformability and sticky RBC aggregates compared with the general population [2,26]. A slight reduction in RBC deformability in exercising healthy athletes and horses has been reported to be associated with the occurrence of EHD in these populations [27,28].…”

“…[31] This finding is possibly attributable to the cross-sectional design of this study. Indeed, RBC deformability is highly variable across patients [26], whether treated or not. Nevertheless, the positive correlation observed between the HbF level and RBC deformability supports an indirect role of HbF on EHD, regardless of HU treatment.…”

An experimental erythrocyte rigidity index (Ri) and its correlations with Transcranial Doppler velocities (TAMMV), Gosling Pulsatility Index PI, hematocrit, hemoglobin concentration and red cell distribution width (RDW)

“…The technique considered the gold standard [43] for measurement of RBC is laser ektacytometry. Although progress has been made in evaluating a population of heterogeneous (deformable and non-deformable) erythrocytes [44,45] the presence of rigid red blood cells interferes with the results, and this fact recognized since the introduction of the technique [46]. Developed decades ago [47] very few laser ektacytometry pieces of equipment do exist at hemocenters of middle-and low-income countries but with a high incidence of SCA patients or related hemoglobinopathies.…”

Multifocal electroretinogram findings in sickle cell maculopathy

“…In SCD patients with both HbS and HbC (HbSC genotype), HbC may form crystal upon oxygenation and promote RBC dehydration, increasing the ability of HbS to form polymers under deoxygenated condition (Brittenham, Schechter, & Noguchi, 1985;Bunn, 1997). HbSC patients are less anemic than HbSS patients but are also characterized by impaired RBC rheology (Nagel, Fabry, & Steinberg, 2003;Renoux et al, 2016). In addition, these sickled RBCs have increased adhesiveness to the vascular wall, leading to a broad range of acute and chronic clinical complications affecting various organs, including the eyes (Ballas, 2018).…”