Red Cell Distribution Width for Predicting Cardiovascular Disease: A Literature Review

Abstract

Although the classical risk factors for cardiovascular disease (CVD) are very important, identification of potential novel risk factors could help clarify CVD pathophysiology, offer novel targets for intervention, and lead to improved risk stratification. Erythrocytes, or red blood cells (RBCs), are constituents of clots and thrombi formed in vivo but little is known about whether inherent properties of RBCs could affect the risk for CVD. The red cell distribution width (RDW) is a measure of the size variation and an index of the heterogeneity of erythrocytes, i.e. anisocytosis. Recently, a large number of studies have found an independent association beyond traditional risk factors between increased RDW (anisocytosis) and CVD. For instance, increased RDW has been associated with different CVDs such as coronary heart disease, stroke, heart failure, atrial fibrillation, peripheral artery disease, pulmonary arterial hypertension, and venous thromboembolism. RDW has also been associated with overall and cardiovascular mortality in different populations. RDW is influenced by many factors including traditional risk factors for CVDs, and it remains to be determined whether RDW is only a biomarker or also a pathogenic mediator for certain CVDs. Future Mendelian randomisation studies may provide a method for assessing the causal nature of increased RDW. Still, RDW is an inexpensive test measured routinely by automated blood cell counters and could be a useful predictor for CVD. In this article we present an overview of the literature about RDW and its association with CVDs.