Relationship of serum NLR and PLR levels with early renal damage in patients with pre-eclampsia

Abstract

Objective To investigate the relationship of neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) with early renal damage in pre-eclampsia (PE) patients. Methods A total of 98 PE patients (PE group) and 113 patients with gestational hypertension (GH, GH group) admitted to our hospital from January 2020 to February 2022 were recruited, and another 68 healthy pregnant women who underwent regular pregnancy examination in our hospital were enrolled as control group. Serum NLR, PLR, and renal function indicators [urea nitrogen (BUN), serum creatinine (Scr), cystatin C (Cys-C) and estimate glomerular filtration rate (eGFR)] were recorded in the 3 groups. According to whether renal injury occurred, the patients of the PE group were divided into non-renal injury subgroup (56 cases) and renal injury group (42 cases). The relationships of NLR and PLR with renal function indicators were analyzed, and the results were further analyzed for the risk factors. The predictive values of NLR and PLR for early renal injury in PE patients were analyzed. Results The levels of NLR, BUN, Scr, Cys-C and 24-h urine protein were significantly higher in the GH group and the PE group than the control group(P < 0.05), and those in the PE group were obviously higher than those in the GH group (P < 0.05). The levels of PLR and eGFR were statistically lower in the GH group and PE group than those in the the control group, and that in the PE group was decreased than that in the GH group (P < 0.05). Pearson correlation analysis showed that NLR was positively correlated with BUN, Scr, Cys-C and 24-h urine protein, and negatively with eGFR, while PLR was negatively correlated with above renal function indicators, and positively with eGFR. Multivariate analysis indicated that severe PE, NLR, PLR, 24-h urine protein and eGFR were the main risk factors for early renal injury in PE patients (P < 0.05). Receiver operating characteristic (ROC) curve analysis showed that the cut-off values of NLR and PLR for predicting early renal injury in PE patients were 2.71 and 103.26, the area under the curve value was 0.896 and 0.809, the sensitivity was 93.28 % and 90.81 %, and the specificity was 80.17% and 80.01%, respectively. Conclusion Elevated levels of NLR and PLR are associated with early renal damage in PE patients, and they are risk factors and have high predictive values for early kidney damage in PE patients.

Keywords

• pre-eclampsia
• early renal impairment
• neutrophil to lymphocyte ratio
• platelet to lymphocyte ratio