ABSTRACT
BACKGROUND: Diabetic nephropathy is the leading cause of end-stage renal disease (ESRD). Anemia is common in diabetics with nephropathy; however, the impact of anemia on progression to ESRD has not been carefully examined. METHODS: We studied the relationship between baseline hemoglobin concentration (Hb) and progression of diabetic nephropathy to ESRD in 1513 participants enrolled in Reduction in Endpoints in NIDDM with the Angiotensin II Antagonist Losartan study and followed for an average of 3.4 years. Multivariate Cox proportional hazards models were used to analyze the relationship between Hb and ESRD, after adjusting for predictors for ESRD. Analyses were performed with Hb stratified by quartile: first quartile <11.3 g/dL, second quartile 11.3 to 12.5 g/dL, third quartile 12.6 to 13.8 g/dL, and fourth quartile >/=13.8 g/dL (reference) and as a continuous variable. RESULTS: Baseline hemoglobin concentration was correlated with subsequent development of ESRD. After adjustment for predictors of ESRD, the hazard ratios for the first, second, and third Hb quartiles were 1.99 (95% CI, 1.34-2.95), 1.61 (95% CI 1.08-2.41), and 1.87 (95% CI 1.25-2.80). With hemoglobin as a continuous variable, the adjusted hazard ratio was 0.90 (95% CI 0.84-0.96, P= 0.0013). The average increase in adjusted relative risk was 11% for each 1 g/dL decrease in hemoglobin concentration. CONCLUSION: Our data suggest that even mild anemia, Hb <13.8 g/dL increases risk for progression to ESRD. Hemoglobin is an independent risk factor for progression of nephropathy to ESRD in type 2 diabetes.
Subject(s)
Anemia/mortality , Diabetes Mellitus, Type 2/mortality , Diabetic Nephropathies/mortality , Kidney Failure, Chronic/mortality , Aged , Anemia/etiology , Antihypertensive Agents/administration & dosage , Diabetes Mellitus, Type 2/complications , Diabetic Nephropathies/complications , Diabetic Nephropathies/drug therapy , Disease Progression , Female , Hemoglobins , Humans , Incidence , Kidney Failure, Chronic/complications , Kidney Failure, Chronic/drug therapy , Losartan/administration & dosage , Male , Middle Aged , Prospective Studies , Risk FactorsABSTRACT
Outcome studies in diabetic nephropathy have focused on strategies to prevent progression of diabetic nephropathy, the leading cause of ESRD in the United States. Once diabetics develop overt nephropathy, prognosis is poor. Risk factors for diabetic nephropathy are discussed, and include hyperglycemia, hypertension, angiotensin II, proteinuria, dyslipidemia, smoking, and anemia. Major outcomes as well as outcome studies in diabetic nephropathy for patients with microalbuminuria and macroalbuminuria are reviewed. Furthermore, the role of therapy with angiotensin converting enzyme inhibitors, angiotensin II receptor blockers, calcium channel blockers, and mineralocorticoid receptor antagonists as well as selected combination therapy are discussed. Recommendations for therapy with ace inhibitors and angiotensin II receptor blockers are made based on this evidence.
