The Prognostic Impact of Dynamic Change in Neutrophil to Lymphocyte Ratio in Patients with Acute Pulmonary Embolism

Abstract

Aim: It is unclear whether temporal changes in neutrophil to lymphocyte ratio (NLR) are associated with total mortality in acute pulmonary embolism (APE). We investigated the value of dynamic monitoring of NLR for the prognosis in patients with APE. Methods: We retrospectively analyzed 214 consecutive APE patients. The patients were divided into two groups: survivors or non-survivors. The neutrophil count, lymphocyte count and NLR were obtained at admission and 72 hours. The difference between the 2 measurements was considered as the NLR change (?NLR). The end point of the study was total mortality at 30-day follow-up. Results: During follow-up, there were 30 deaths (14%). ?NLR was higher in non-survivors than survivors survivors (5.22 [0.62-7.76] vs -0.71 [-2.28-0.76], P < .001). In multivariate analysis, the ?NLR was found to be a significant predictor of 30-day mortality (OR: 1.059, 95% CI:1.021-1.098, p=0.002). For 30-day mortality, the area under the curve (AUC) of Simplified Pulmonary Embolism Severity Index (sPESI) score was 0.719 (95% CI:0.630-0.809, p < 0.001). When ?NLR was added to sPESI score, the AUC was 0.841 (95% CI: 0.769-0.913, difference p = 0.0008, Fig.1). Morever, the addition of ?NLR to sPESI score was associated with a significant net reclassification improvement estimated at 68.9% (p < 0.001) and an integrated discrimination improvement of 0.108 (p = 0.0046). Conclusion: Our findings show that an increase in NLR after admission was independently associated with total mortality in patients with APE.