Relationship between prognostic nutritional index and contrast-induced nephropathy in patients presenting with acute coronary syndrome

Objectives: This study aimed to evaluate malnutrition with the prognostic nutritional index (PNI) and investigate its association with contrast-induced nephropathy (CIN). Patients and methods: The retrospective cohort study was conducted with 162 acute coronary syndrome (ACS) patients (113 males, 49 females; mean age: 58.6±12.6 years; range, 26 to 92 years) admitted between Novomber 2016 and September 2017. The patients were divided into two groups according to laboratory, angiographic, demographic, and echocardiographic parameters: those with CIN (n=16) and those without CIN (n=146). The data were obtained from the hospital system, and patients with complete parameters were included in the study. The PNI score was computed by multiplying the total lymphocyte count (mm3) by 0.005 and adding it to 10 times the serum albumin (g/dL). Results: Twenty-one (12.9%) of the patients had non-end-stage renal failure before the procedure, and the development of CIN was significantly higher in those with baseline renal dysfunction (50% vs. 8.9%, p<0.001). The PNI was significantly lower in the group that developed CIN (43.5±5.5 vs. 50.4±8.7, p=0.002). In-hospital mortality occurred in six (3.7%) of 162 patients who underwent PCI due to myocardial infarction. The mortality rate was significantly higher in the CIN group (18.8% vs. 2.1%, p=0.01). In the receiver operating characteristic analysis, a PNI <46 had 69% sensitivity and 75% specificity (area under the curve=0.76, 95% confidence interval 0.646-0.879, p=0.001) for determining CIN. Conclusion: In conclusion, this study demonstrated that PNI, a marker of nutritional status, may be a reliable predictor of contrast nephropathy in patients presenting with ACS.