Impact of renal function on patients with acute coronary syndromes: 15,593 patient-years study.

Introduction: Coexistence of chronic kidney disease (CKD) in the case of acute coronary syndromes (ACS) significantly worsens the outcomes.
Aim: The aim of our study was to assess renal function impact on mortality among patients with ACS.
Materials and Methods: The study was based on records of 21,985 patients hospitalized in the Medical University of Bialystok in 2009-2015. Inclusion criteria were ACS. Exclusion criteria were: death within 24 h of admission, eGFR <15 ml/min/1.73 m ² , hemodialysis. Mean observation time was 2296 days.
Results: Criteria were met by 2213 patients. CKD occurred in 24.1% ( N  = 533) and more often affected those with NSTEMI (26.2 (337) vs. 21.2 (196), p  = .006). STEMI patients had higher incidence of post-contrast acute kidney injury (PC-AKI) (5 (46) vs. 4.1 (53), p  < .001). During the study, 705 people died (31.9%), more often with NSTEMI (33.2% (428) vs. 29.95% (277), p  < .001). However, from a group of patients suffering from PC-AKI 57.6% died. The risk of PC-AKI increased with creatinine concentration (RR: 2.990, 95%CI: 1.567-5.721, p  < .001), occurrence of diabetes mellitus (RR: 2.143, 95%CI: 1.029-4.463, p  = .042), atrial fibrillation (RR: 2.289, 95%CI: 1.056-4.959, p  = .036). Risk of death was greater with an increase in postprocedural creatinine concentration (RR: 2.254, 95%CI: 1.481-3.424, p  < .001).
Conclusion: PC-AKI is a major complication in patients with ACS, occurs more frequently in STEMI and may be a prognostic marker of long-term mortality in patients undergoing percutaneous coronary intervention (PCI). More attention should be given to the prevention and diagnosis of PC-AKI but necessary PCI should not be withheld in fear of PC-AKI.