Prevalence, etiology, and consequences of anemia and clinical and economic benefits of anemia correction in patients with chronic kidney disease: an overview.

PURPOSE: The prevalence of chronic kidney disease (CKD) and anemia in the United States, classification scheme for CKD, definition of anemia, etiology and consequences of anemia in patients with CKD, and the clinical and economic benefits of correcting anemia are described.
SUMMARY: Approximately 20 million people in the United States population have CKD, and 2-4 million of these may also have anemia, which often goes undetected and untreated. Patients with CKD are now classified into five stages based on the degree of kidney function impairment. Here, anemia is caused by insufficient erythropoietin production, and may occur as early as stage 3 CKD. Potential consequences of anemia include cognitive impairment, angina, and the cardiorenal anemia syndrome, a triad of worsening anemia, worsening CKD, and worsening congestive heart failure. Treatment of anemia in predialysis patients with stage 2-4 CKD may slow renal disease progression and improve energy, work capacity, health-related quality of life, and cardiac function. Optimizing the hemoglobin or hematocrit value before initiating dialysis may reduce mortality. Anemia contributes to significant healthcare costs associated with CKD. Substitution of the subcutaneous route of administration for the intravenous route of administration for epoetin alfa can reduce drug acquisition and healthcare costs, the two largest components of healthcare costs in CKD patients. Efforts to slow the progression of CKD could also have a substantial impact on hospitalizations and costs.
CONCLUSION: Correcting anemia has the potential to improve clinical and economic outcomes in patients with CKD.