Incidence and mortality of acute kidney injury in patients with acute coronary syndrome: A retrospective study from a single coronary care unit.

Acute kidney injury (AKI) is associated with adverse short-and long-term outcomes. The aim of this study was to evaluate the incidence of AKI and the short-term mortality in patients admitted with acute coronary syndrome (ACS) to a single coronary care unit (CCU) in Tripoli, Libya. We retrospectively studied the medical records of ACS patients admitted to the CCU of a referral cardiology center, during the period from January 1, 2014, to December 31, 2014. AKI was defined according to the AKI network criteria. The incidence of AKI and short-term CCU mortality was compared between different types of ACS. Data of patients with and without AKI were compared using Student's t-test and Chi-squared statistic considering P <0.05 statistically significant. Eighty-four patients with ACS were included in the study; their mean age was 57.6 ± 14.4 years [standard deviation (SD)], 75% were males and their mean stay in the CCU was 4.3 ± 3 days (SD). Of them, 71.4% had ST-elevated myocardial infarction (STEMI), 22.6% had non-STEMI, and 6% had unstable angina. About 41.7% had AKI (19% had AKI Stage 1, 17.9% had AKI Stage 2, and 4.8% had AKI Stage 3). The total CCU mortality was 15.5%; mortality among AKI patients in the CCU was 25.7% compared with 6.12% in the non-AKI patients (P = 0.014). The mortality worsened with increasing severity of AKI. Patients with AKI were older (61.6 ± 15 years) than the non-AKI group (54.7 ± 13 years, P = 0.031), their mean blood pressure at admission was lower, their CCU stay was longer, and they more frequently had coexisting acute decompensated heart failure. In this study of ACS patients, the incidence of AKI was high, the CCU mortality among the AKI patients was 25.7% compared with 6.12% in the non-AKI patients, and the mortality worsened with increasing severity of AKI.