Objective: Acute myocardial infarction constitutes one of the leading reasons for cardiac mortality. Therefore, early identification of high-risk patients provides better prognostic accuracy. This study aimed to investigate the prognostic significance of novel inflammatory biomarkers such as neutr ophil -to-l ympho cyte ratio, systemic immune-inflammation index, and prognostic nutritional index in acute myocardial infarction patients treated with percutaneous coronary intervention and to compare their predictive abilities with each other.
Methods: A total of 828 acute myocardial infarction patients treated with percutaneous coronary intervention were retrospectively analyzed. The inflammatory indices, such as neutr ophil-to-l ympho cyte ratio, systemic immune-inflammation index, and prognostic nutritional index, were calculated by admission blood tests. The study population was divided into 2 groups according to the occurrence of major adverse cardiac events, which were defined as all-cause mortality, non-fatal myocardial infarction, and cerebrovascular events.
Results: Multivariate Cox regression analysis determined prognostic nutritional index as an independent predictor of major adverse cardiac event and all-cause mortality (hazard ratio: 1.05, 95% CI: 1.02-1.07, P < .001 for major adverse cardiac event and hazard ratio: 1.05, 95% CI: 1.02-1.09, P = .002 for all-cause mortality). Receiver operating characteristic curves revealed that the predictive value of prognostic nutritional index with both regard to major adverse cardiac event and all-cause mortality was better than the systemic immune-inflammation index and neutr ophil -to-l ympho cyte ratio (by DeLong method, area under curvePNI vs. area under curveSII z test = 2.66, P = .008; area under curvePNI vs. area under curveNLR z test = 2.8, P = .006; area under curvePNI vs. area under curveSII z test = 2.58, P = .009; area under curvePNI vs. area under curveNLR z test = 3.28, P = .001; respectively).
Conclusions: Prognostic nutritional index was demonstrated as an independent predictor of major adverse cardiac events and all-cause mortality and a more powerful prognostic index than other novel inflammatory biomarkers in acute myocardial infarction patients treated with percutaneous coronary intervention.