Neutrophil-to-Lymphocyte Ratio as a Predictor of Worsening Renal Function in Diabetic Patients (3-Year Follow-Up Study)

Background: Previous studies have demonstrated the role of inflammation in diabetic nephropathy (DN). Neutrophil to lymphocyte ratio (NLR) rather than other white cell parameters was found to be a useful inflammatory marker to predict adverse outcomes in medical and surgical conditions. Nevertheless, the value of NLR in predicting DN has not been elucidated. Method: An observational study included 338 diabetic patients, who were followed at our clinic between 2007 and 2009. We arranged our patients into tertiles according to their 2007 NLR. The primary outcome was continuous decrease of GFR >12 mL/min between 2007 and 2009 with the last GFR <60 mL/min. Result: The lowest NLR tertile had fewer patients (2.7%) with primary outcome (i.e., worsening renal function) compared with middle and highest NLR tertiles, which had more patients with primary outcomes (8.7% and 11.5%, respectively) with a significant p-value 0.0164. When other potential confounders were individually analyzed with NLR tertile, the NLR tertiles remained a significant predictor of poor GFR outcome in the presence of other variables (hemoglobin A1C, systolic blood pressure, diastolic blood pressure, age, and congestive heart failure with p-values 0.018, 0.019, 0.017, 0.033, and 0.022, respectively). Conclusion: NLR predicted the worsening of the renal function in diabetic patients. Further studies are needed to confirm this result.