Neutrophil Lymphocyte Ratio as an Inflammatory Marker in Chronic Kidney Disease: Determinants and Correlates

Abstract

Introduction: Inflammation has been implicated as a major reason for the higher morbidity and mortality in chronic kidney disease (CKD) compared to the diseases that commonly precedes it. The neutrophil lymphocyte ratio (NLR) has increasingly been reported to be a marker of systemic inflammation. We studied the neutrophil lymphocyte ratio and its relationship with kidney function and other markers of inflammation in health and in CKD. Methods: Two hundred and forty four participants in three cohorts: healthy, CKD stage 1 - 2 and, stage 3 - 4, were studied. Data of clinical, NLR, uric acid, urine albumin creatinine ratio (UACR), electrolytes were documented and independent associates of NLR were determined. Results: The NLR was higher in the CKD cohorts, P < 0.001 and females, P = 0.01. The mean NLR of all participants, the healthy and, CKD cohorts were 2.8 ± 0.7, 1.5 ± 0.6 and 3.9 ± 1.4, P < 0.001. The mean NLR of all participants ≥ 65 years, all males ≥ 65 years and, all females ≥ 65 years were 4.0 ± 1.6, 3.7 ± 1.0 and 4.2 ± 1.2, P = 0.01. The NLR was positively related to the age (P < 0.001), systolic blood pressure (P = 0.012), uric acid (P = 0.018), UACR (P = 0.006) and platelet lymphocyte ratio, P = 0.04. The NLR was negatively related to the hematocrit (P < 0.001), albumin (P < 0.001) and glomerular filtration rate (P < 0.001). Multivariate analysis after ruling out cofounders, showed age (aOR5.8, CI- 4.26 - 10.22), systolic hypertension (aOR1.5, CI-1.21 - 2.07), hyperuricemia (aOR-1.5, CI-0.94 - 2.09), elevated urine ACR (aOR-1.7, CI-1.25 - 2.47) and CKD (aOR-7.2, CI-1.45 - 8.94) as independent predictors of NLR. Conclusion: The NLR as an inflammatory marker is elevated in chronic kidney disease, and increases with disease severity hence it can be a useful tool in determining the presence and severity of inflammation in CKD.