Background: Diabetic nephropathy has become the single most important cause of end-stage renal disease (ESRD) worldwide. Strategies to slow the rate of loss of renal function in these patients have been developed. We examined the risk factors that predict loss of kidney function (doubling of serum creatinine) or ESRD (dialysis or transplantation) in patients with type 2 diabetes in whom blood pressure was controlled.
Methods: We evaluated risk factors for doubling of serum creatinine or the development of ESRD in the Reduction of End Points in NIDDM with the Angiotensin II Receptor Antagonist Losartan (RENAAL) study, which included 1513 patients with type 2 diabetes and nephropathy.
Results: Univariate analyses demonstrated a group of 23 risk factors that significantly predicted doubling of serum creatinine or ESRD. From these univariate analyses, a multivariate model was developed that demonstrated four independent risk factors: proteinuria, serum creatinine, serum albumin, and hemoglobin level. Proteinuria was the strongest and most consistent risk factor. The multivariate risk model was derived from only the placebo group and was similar to that derived for the total population, suggesting that the risk predictors for progression of kidney disease were independent of therapy.
Conclusion: After control of blood pressure in type 2 diabetic patients with nephropathy, proteinuria, degree of renal failure, serum albumin, and hemoglobin level are independent risk factors that predict renal outcomes. The level of proteinuria proved to be the most important risk for progressive kidney injury in these diabetic patients.