Renal function estimationandone-yearmortalityinelderlypatients with non-ST-segment elevation acute coronary syndromes

Chronic renal dysfunction is relatively common in patients hos-pitalized for acute coronary syndrome (ACS) and is among themost powerful predictors of adverse in-hospital outcomes[1].Mathematical estimations of glomerularfiltration rate (GFR),based on serum creatinine concentration, have emerged as a clini-callyusefulmethodtomoreaccuratelymeasurerenalfunction.TheCockcroft–Gault (CG) equation has beenthe traditional method ofestimatingGFRfordrugdosing[2].Morerecently,theModificationof Diet in Renal Disease (MDRD) formula and the Chronic KidneyDisease Epidemiology Collaboration (CKD-EPI) equation havebeen developed and shown to perform better than the CG equationin terms of precision and accuracy[3]. However, neither >formulawas specifically developed or validated in patients with heartdiseases, especially the elderly and the very elderly[2].TheItalian Elderly ACS study, thefirst specifically investigating treat-ment strategies for elderly patients with non ST-elevation ACS(NSTEACS), represents a unique opportunity to investigate thisissue. Details of the study design and population have been pub-lished[4]. Overall 645 patients aged≥75 years were enrolled inthe trial or included in a parallel registry. Signature of an informedconsent form was a prerequisite for enrolment. The study protocolconformed to the ethical guidelines of the 1975 Declaration ofHelsinki as reflected in a priori approval by the institution'shuman research committee. Serum creatinine (Cr) was analyzedaccording to the method used in each local laboratory. TheGFR from the CG equation was estimated as: ([{140− age inyears}×bodyweightinkg]/{72×Crinmg/dl})×0.85(femalegender); for the MDRD formula as: [186 × (Cr in mg/dl)