Association Between Neutrophils and Renal Impairment of Rheumatoid Arthritis: A Retrospective Cross-sectional Study

Abstract

Objective Whether neutrophil could be a risk factor of renal impairment in rheumatoid arthritis (RA) remains unclear. Therefore, we aimed to investigate the prevalence of renal impairment in RA and determine its correlation with neutrophils. Methods We retrospectively investigated renal function of 602 RA patients in the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine by estimated glomerular filtration rate (GFR). Potential risk factors for renal dysfunction were collected in all RA patients. We used univariate and multivariate logistic regression analysis to evaluate association between neutrophils and renal impairment. Results A total of 89 cases (14.8%) had renal impairment with GFR < 60 ml/min/1.73 m2, and 75 cases (84.3%) were female. Compared to RA patients with normal renal function, age, white blood cell count, serum levels of triglyceride, uric acid, C-reactive protein level, erythrocyte sedimentation rate, Cystatin-C, and creatinine in those with renal impairment increased, but red blood cell count and hemoglobin level decreased (all p < 0.05). Adjusted for numerous potential confounders, multivariate analysis indicated that neutrophils > 7.5 × 10^9/L (OR = 1.7, 95% CI: 1.03 to 2.98), hemoglobin < 120 g/L (OR = 2.4, 95%CI: 1.360 to 4.281), and uric acid > 360umol/l (OR = 6.1, 95%CI: 3.71 to 10.10) significantly correlated with a higher risk of renal impairment. Conclusions Neutrophil count > 7.5 × 10^9/L may be associated with a high risk of renal impairment in RA. Prospective studies are needed to verify our results.