Plasma Concentrations of Cystatin C in Patients with Coronary Heart Disease and Risk for Secondary Cardiovascular Events: More Than Simply a Marker of Glomerular Filtration Rate (Proteomics and Protein Markers) (Clinical Report‪)‬

There is an increasing burden of chronic renal impairment (RI) [3] in the general population (1). In addition, RI is often not recognized and treated adequately (2-4). Individuals with RI have a high risk for end-stage renal disease, a condition requiring dialysis or transplantation to avoid uremia (5). It is also evident that RI is an independent risk factor for cardiovascular disease (CVD), congestive heart failure, and total mortality (1, 6, 7). Furthermore, in numerous studies including patients with manifest CVD or diabetes (8) and congestive heart failure (9), a decreased glomerular filtration rate (GFR) has been found to be an independent risk factor for future CVD events and total mortality, even in cases in which RI was mild (1). In addition, percutaneous coronary interventions have a less favorable outcome if conducted in patients with RI (10). Therefore, early identification of patients with RI is of utmost interest because preventive and renoprotective measures are available. In clinical practice, GFR is assessed by measurement of serum or plasma creatinine (Cr) or by determination of creatinine clearance (CrCI) (1). However, serum Cr is of limited value in early detection of RI, and CrCl overestimates true GFR because Cr is not only filtered by the glomeruli but is also secreted by the tubules (11).