Distribution and reference interval establishment of neutral-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) in Chinese healthy adults

Abstract

Background: Neutral-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), and platelet-to-lymphocyte ratio (PLR) are associated with coronavirus disease 2019 (COVID-19) and many diseases, but there are few data about the reference interval (RI) of NLR, LMR, and PLR. Methods: The neutrophil count, lymphocyte count, monocyte count, and platelet count of 404,272 Chinese healthy adults (>18 years old) were measured by Sysmex XE-2100 automatic hematology analyzer, and NLR, LMR, and PLR were calculated. According to CLSI C28-A3, the nonparametric 95% percentile interval is defined as the reference interval. Results: The results of Mann-Whitney U test showed that NLR (p 80 group, and PLR in 70–79 group appeared a trough; the reference upper limit of NLR in >80 group, LMR in 50–59 group, and PLR in 40–49 group appeared peak. Conclusion: The establishment of RI for NLR, LMR, and PLR in Chinese healthy adults according to gender and age will promote the standardization of clinical application.