An Elevated Neutrophil-Lymphocyte Ratio Increases the Risk of Cardiovascular Events and of Renal Function Decline in Hypertensive Patients with CKD

Abstract

Introduction: Many epidemiological studies have shown that low-grade chronic inflammation, estimated through the neutrophil-lymphocyte ratio (NLR), is linked to traditional and non-traditional cardiovascular (CV) risk factors. Aim: The aim of our study was to investigate the potential prognostic role of NLR regarding the progression of chronic kidney disease (CKD) and the development of CV events in a cohort of renal and hypertensive patients. Methods: In this retrospective observational study, 403 patients consecutively attending our Nephrology and Hypertension clinics were included. At the baseline observation and control visits in all patients, in addition to the clinical-anamnestic evaluation, and the measurement of blood pressure values and anthropometric indices, a complete blood count and biohumoral data regarding renal function, lipid profile and to serum electrolytes were obtained. Results: Median follow-up time was 38.95 [27-75] months. Patients were divided into two groups based on an NLR cut-off of 1.96, which resulted from the analysis of ROC curves as the optimal NLR value for identifying patients at greatest risk of CV events. During the observation period 103 CV events occurred, 72 of which were in the group with the highest NLR. Analyzing the ROC curves, an NLR value of 1.96 was found to have a sensitivity of 78.7% and a specificity of 51.7% (AUC = 0.672, P = < 0.0001) in predicting the CV outcome.Multivariate Cox regression analyses showed that an NLR> 1.96 predicted CV events, even after correction for gender, BMI, diabetes, BP values, dyslipidemia and hyperuricaemia (HR: 2.54; p = 0.0003). A more rapid progression of renal disease (defined as an annual decline in GFR> 3 ml/min/m2) was observed in 170 patients. The ability of an NLR > 1.96 to predict the risk of CKD progression was found to be independent of age, sex, obesity, dyslipidemia, hyperuricaemia, diabetes and BP values (HR: 1.60, p = 0.0123). An NLR value of 1.96 was found to have a sensitivity of 74% and a specificity of 63% (AUC = 0.582; p = 0.0054) in predicting a more rapid decline in renal function. Conclusions: In conclusion, the results of our study suggest that, in patients with CKD, an elevated neutrophil/lymphocyte ratio represents an independent predictor not only of the development of cardiovascular events, but also of a more rapid progression of renal disease.