Erythropoietic stress and anemia in diabetes mellitus

Chronic hyperglycemia in diabetes mellitus can lead to erythropoietic stress and subsequent anemia, which might contribute to diabetes-related complications. The authors of this Review discuss the various causes of diabetes-related anemia and current guidelines on its correction, and emphasize the role of screening and monitoring for this preventable condition in patients with diabetes mellitus. Anemia is one of the world's most common preventable conditions, yet it is often overlooked, especially in people with diabetes mellitus. Diabetes-related chronic hyperglycemia can lead to a hypoxic environment in the renal interstitium, which results in impaired production of erythropoietin by the peritubular fibroblasts and subsequent anemia. Anemia in patients with diabetes mellitus might contribute to the pathogenesis and progression of cardiovascular disease and aggravate diabetic nephropathy and retinopathy. Anemia occurs earlier in patients with diabetic renal disease than in nondiabetic individuals with chronic kidney disease. Although erythropoietin has been used to treat renal anemia for nearly two decades, debate persists over the optimal target hemoglobin level. Most guidelines recommend that hemoglobin levels be maintained between 105g/l and 125g/l. The suggested role of anemia correction—to prevent the progression of left ventricular hypertrophy in patients with diabetes mellitus—is yet to be established. However, an emphasis on regular screening for anemia, alongside that for other diabetes-related complications, might help to delay the progression of vascular complications in these patients. Key Points Anemia is a common complication of diabetes mellitus and an independent contributor to the pathogenesis and progression of other diabetes-related complications Erythropoietic stress in diabetes mellitus might be caused by elevated levels of advanced glycation end products, oxidative stress, endothelial dysfunction, abnormal red blood cells and reduced bioavailability of nitric oxide Anemia occurs earlier in patients with diabetic nephropathy than in nondiabetic individuals with comparable renal function In patients with diabetes mellitus, correction of anemia improves quality of life and might delay the progression of diabetic complications; therefore, routine screening for anemia is recommended in this population Until definitive evidence of optimal hemoglobin levels is available, treatment should aim to achieve levels of 105g/l–125g/l