Anemia, Diabetes, and Chronic Kidney Disease

Diabetes is the leading cause of chronic kidney disease (CKD) and is associated with excessive cardiovascular morbidity and mortality (1,2). Anemia is common among those with diabetes and CKD and greatly contributes to patient outcomes (3,4). Observational studies indicate that low Hb levels in such patients may increase risk for progression of kidney disease and cardiovascular morbidity and mortality (5). Controlled clinical trials of anemia treatment with erythropoietin stimulating agents (ESAs) demonstrated improved quality of life (QOL) but have not demonstrated improved outcomes (6–10). In some trials, ESA treatment for high Hb levels is associated with worse outcomes such as increased thrombosis risk (6,11). Consequently, the U.S. Food and Drug Administration (FDA) and the National Kidney Foundation (NKF) have modified their recommendations regarding anemia treatment for CKD patients (12). The objectives of this review are to 1 ) update clinicians on the prevalence, causes, and clinical consequences of anemia; 2 ) discuss the benefits and risks of treatment; and 3 ) provide insight into anemia management based on clinical trial evidence in patients with diabetes and kidney disease who are not on dialysis. The NKF defines anemia in CKD as an Hb level <13.5 g/dl in men and 12.0 g/dl in women (13). This definition is based on the fact that these levels are outside the 95% CIs of the mean for normal men and women. Anemia is common in diabetic patients with CKD (5). It is estimated that one in five patients with diabetes and stage 3 CKD have anemia, and its severity worsens with more advanced stages of CKD and in those with proteinuria (7,14,15) For example, in a 5-year prospective observational study conducted in a diabetes clinic in Australia, anemia was found in early kidney disease, and declining …