Prognostic nutritional index and the risk of acute kidney injury in patients with acute coronary syndrome

OBJECTIVE: Recent studies have linked malnutrition with undesirable outcomes in cardiovascular diseases. However, the underlying mechanism is unknown. Contrast-induced acute kidney injury (CI-AKI) increased cardiovascular mortality after percutaneous coronary intervention (PCI). This study hypothesizes that prognostic nutritional index (PNI) plays a role in the development of CI-AKI in patients with acute coronary syndrome undergoing emergency PCI. METHODS: This study enrolled 551 patients. PNI was determined as 10x serum albumin (g/dL)+0.005xtotal lymphocyte count (mm(3)). CI-AKI was characterized as the increase in serum creatinine >= 0.3 mg/dL level within 48 h after PCI. Patients were classified as either CI-AKI (+) or CI-AKI (-). RESULTS: CI-AKI has occurred in 72 of 551 patients (13.1%). PNI was significantly lower in the CI-AKI (+) group than in the CI-AKI (-) group (44.4 +/- 6.6 versus 47.2 +/- 5.8, p<0.001, respectively). Multivariate logistic regression analysis showed that PNI [odds ratio, OR: 1.631, 95% confidence interval (CI): 1.168-2.308, p=0.02] and estimated glomerular filtration rate (OR: 3.26, 95%CI 1.733-6.143, p<0.001) were independent risk factors for CI-AKI. CONCLUSIONS: PNI is an independent risk factor for CI-AKI. The development of CI-AKI may be the mechanism responsible for the relationship between poor nutritional status and adverse cardiac events.