Association between the platelet-lymphocyte ratio and short-term mortality in patients with non-ST-segment elevation myocardial infarction.

ABSTRACT

BACKGROUND: Previous studies have shown that inflammation plays an important role in atherosclerosis and cardiovascular disease. Platelet to lymphocyte ratio (PLR) has been reported as a novel inflammatory marker. However, it is not clear whether PLR is associated with short-term all-cause mortality in critically ill patients with non-ST-segment elevation myocardial infarction (NSTEMI). METHODS: The data for the study is from the Medical Information Mart for Intensive Care III database. The primary outcome in our study was 28-day mortality. Kapan-Meier curve, lowess smoother curve, and multivariate Cox regression models were used to determine whether the association between PLR and 28-day mortality of critically ill patients with NSTEMI. RESULTS: A total of 1273 critically ill patients with NSTEMI were included in this analysis. Kapan-Meier curve and lowess smoother curve show that high PLR is associated with an increased risk of 28-day all-cause mortality. The study population is divided into two groups according to the cut-off value of PLR level. In the Cox model, high PLR levels (PLR≥195.8) were significantly associated with increased 28-day mortality (HR 1.54; 95%CI 1.09-2.18, p = .013). In quartile analyses, the HR (95% CI) for the third (183 ≤ PLR < 306) and fourth quartile (PLR≥306) was 1.55 (1.05-2.29) and 1.61 (1.03-2.52), respectively, compared to the reference group(111 ≤ PLR < 183). In subgroup analyses, there is no interaction effect in most of the subgroups except for respiratory failure and vasopressor use. CONCLUSION: High PLR is associated with an increased risk of short-term mortality in critically ill patients with NSTEMI.