Epidemiology and Risk Factors for Chronic Kidney Disease in Chinese Patients with Biopsy‐proven Lupus Nephritis

BackgroundLupus nephritis (LN) is one of the most serious complications of systemic lupus erythematosus (SLE). It is the most common secondary glomerulonephritis leading to end-stage renal disease.AimThe purpose of this study is to evaluate the epidemiology and risk factors of chronic kidney disease (CKD) in Chinese patients with LN.MethodsClinical, laboratory, renal histopathology, treatment and outcome data were collected and retrospectively analysed in LN patients with or without CKD.ResultsAt the end of the study, 94 (45.63%) patients were identified as having CKD among 206 individuals with renal biopsy-proven LN. Renal function, represented by serum creatinine and estimated glomerular filtration rate, was significantly decreased in the CKD patients (P = 0.008 and P < 0.001, respectively) at the time of the kidney biopsy. Compared with the non-CKD group, significantly increased proportions of hypertension (P < 0.001), serositis (P = 0.042) and anti-histone antibody positivity (P = 0.004) were detected in the CKD patients. Renal pathological activity and chronicity index scores were significantly increased in the CKD group (P < 0.001 for all). Finally, hypertension (hazard ratio (HR) 2.432, 95% confidence interval (CI) 1.575-3.754, P < 0.001), anti-histone antibody (HR 2.907, 95% CI 1.837-4.600, P < 0.001), and tubular atrophy (HR 1.248, 95% CI 1.007-1.547, P = 0.043) were independent risk factors for CKD.ConclusionsHypertension, anti-histone antibody and tubular atrophy are independent risk factors for CKD in Chinese LN patients.