Monitoring Kidney Function and Albuminuria in Patients With Diabetes

It is beyond doubt that patients with diabetes are at high risk of developing renal and cardiovascular disease. Both outcomes have significant clinical implications and are associated with high additional costs. Several traditional (blood pressure, HbA1c, cholesterol) and novel cardiovascular biomarkers (C-reactive protein, pro-brain natriuretic peptide) are at hand to identify those individuals who will develop end-stage renal or cardiovascular disease, as early as possible. The traditional biomarkers have been successfully applied in clinical practice and have proven their clinical usefulness. Renal biomarkers, in particular, albuminuria and estimated glomerular filtration rate (eGFR), have been added to the biomarker armamentarium. Both are indeed associated with renal and cardiovascular disease in individuals with diabetes and may be used to identify individuals at risk of long-term complications. Although identifying individuals at risk is important, even more important is the question whether we can lower this risk by changing renal biomarkers through pharmacological (or other) intervention. This overview describes the performance of albuminuria and eGFR in predicting renal and cardiovascular disease. In the second part, the relationship between treatment-induced changes in these two renal biomarkers and renal and cardiovascular outcome will be described. ### Albuminuria The relationship between albuminuria and renal and cardiovascular disease has been well established. Its association was first described in patients with type 1 diabetes (1,2). Several studies followed these initial reports and confirmed the significance of albuminuria in predicting long-term renal prognosis. Data from prospective trials showed that patients with type 2 diabetes appear to progress from micro- to macroalbuminuria to end-stage renal disease (ESRD), similar to the earlier reports of patients with type 1 diabetes. The Reduction in End Points in Non-Insulin Dependent Diabetes Mellitus With the Angiotensin II Antagonist Losartan (RENAAL) showed that albuminuria is the most critical baseline predictor for ESRD (3). Similar data …