To determine the association between baseline creatinine clearance (CrCl), coronary revascularization during index admission, and 1-year mortality in elderly patients with an acute coronary syndrome (ACS). METHODS AND RESULTS: We estimated CrCl using the Cockcroft-Gault (CG) formula in 313 patients aged ≥75 years enrolled in a prospective study of treatment strategies in non ST-elevation ACS (NSTEACS). Patients were stratified into four groups according to CrCl on admission (using a cutoff of 45 ml/min) and coronary revascularization versus medical management. The mean age of the study population was 81 years and the median serum creatinine level on admission was 1.0 mg/dl (interquartile range (IQR) 0.8-1.3). Patients with impaired renal function treated medically had higher in-hospital and 1-year mortality, especially if compared with patients with preserved renal function undergoing revascularization (1-year mortality 22.9% versus 4.9%). Across the spectrum of CrCl categories, coronary revascularization was independently associated with a lower risk of mortality (HR 0.405; 95% CI 0.174-0.940; p=0.035). CONCLUSIONS: In elderly patients with NSTEACS, coronary revascularization decreases the risk of 1-year death across each CrCl category, and is one of the most powerful predictors of 1-year outcome.