Chronic kidney disease in Korean patients with lupus nephritis: over a 35-year period at a single center

Introduction Chronic kidney disease (CKD) is a major risk factor for overall morbidity and mortality even in lupus nephritis (LN) patients. However, less attention has been paid to the development of CKD in patients with LN. The objective of this study was to identify predictors for CKD with 35-year experience depending on newly revised guidelines for patients with LN. Methods We conducted a retrospective cohort study for 401 patients who visited Seoul St. Mary's Hospital between January 1985 and December 2019. We analyzed clinical and laboratory indices, treatment response, the final renal function, and biopsy findings. The timing and cumulative risk of developing CKD were identified by Kaplan-Meier methods. Independent risk factors for developing CKD were examined by Cox proportional hazard regression analyses. Results The median follow-up time after the diagnosis of LN was 131 months. CKD occurred in 15.5% of patients within 10 years after the diagnosis of LN. The development of CKD was associated with delayed-onset LN, acute renal dysfunction at onset of LN, and failure to reach complete response (CR) at 6 or 12 months rather than histopathological findings or the severity of proteinuria at onset of LN. Cumulative incidence of progression to CKD was significantly higher in patients with the three predictors mentioned above. Conclusion Ten-year cumulative incidence of CKD was about 15%. Our results showed that delayed-onset LN, acute renal dysfunction at the onset of LN, and inadequate treatment response assessed at 6 or 12 months after treatment were predictors for the development of CKD in LN.