Estimation of glomerular filtration rate in cardiorenal patients: a step forward

The progressive reduction in estimated glomerular filtration rate (eGFR) resulting in chronic kidney disease (CKD) is associated with increased risk of cardiovascular disease (CVD) (i.e., cardiorenal disease). Cardiorenal disease is associated with poor outcomes, mainly due to increased cardiovascular (CV) complications and CV death. Data from general population-based studies and studies of cohorts with CKD and/or CVD show that compared with creatinine-based eGFR, cystatin C-based eGFR and creatinine plus cystatin C-based eGFR detect higher risks of adverse CV outcomes and add predictive discrimination to current CVD risk scores. On the other hand, growing clinical evidence supports kidney and CV protective effects of sodium-glucose cotransporter-2 (SGLT2) inhibitors in cardiorenal patients. However, recent data suggest that some detrimental effects of SGLT2 inhibitors on skeletal muscle mass may lead to overestimation of creatinine-based eGFR and subsequent misinterpretation of associated CV risk in patients treated with these agents. Within this framework, we suggest the advisability of using cystatin C and/or creatinine plus cystatin C-based eGFR for routine clinical practice in cardiorenal patients to more accurately stratify CV risk and evaluate the kidney and CV protective effects of SGLT2 inhibitors. In this regard, we make a call to action to investigate the protective effects of these pharmacological agents using cystatin C-based eGFR.