HIGH platelet-to-lymphocyte ratio (PLR) in patients hospitalised with acute myocardial infarction could indicate an up to three times higher risk of experiencing major adverse cardiovascular events in the 30 days following percutaneous coronary intervention. The PLR, which is calculated by dividing absolute platelet count by absolute lymphocyte count, is a novel inflammatory marker that could be used to predict inflammation and mortality in multiple disorders. Previous studies have shown that there is a correlation between PLR and coronary artery disease, suggesting that it may be used as a predictor of coronary artery disease, major adverse cardiac events, or mortality.
Yi Ma, Tangshan Gongren Hospital, China, and colleagues conducted a study analysing data from nearly 800 patients who were hospitalised with acute myocardial infarction and underwent a successful primary percutaneous coronary intervention within 12 hours of the onset of chest pain. The patients were stratified by high and low PLR groups using a PLR cut-off value of 178. Total white blood cell, lymphocyte, platelet, and neutrophil count were assessed on admission. The primary outcome of the study was major adverse cardiovascular events at 30 days.
Data showed that those with a high PLR were more likely to experience non-fatal myocardial infarction (6.94% versus 2.35%), major adverse cardiovascular events (15.28% versus 4.7%), or cardiovascular death (8.33% versus 2.35%) compared with patients with a low PLR. The incidence of reinfarction, major adverse cardiovascular events, and death, were approximately three times higher in those with a high PLR compared with the group with low PLR. Logistic regression analysis showed that age, PLR, and hypertension status were independent predictors of adverse outcomes. Furthermore, PLR of 178 or higher predicted adverse outcomes with a sensitivity of 65% and specificity of 73%, following analysis of the receiver operating characteristic curve.
The researchers concluded: “These findings showed that the PLR might be regarded as a potentially accessible, dependable, and affordable criterion for risk stratification and categorisation in acute myocardial infarction patient groups.”