Incidence of relapse and frequently relapsing/steroid-dependent nephrotic syndrome in Chinese children with steroid-sensitive nephrotic syndrome: A cohort study

Abstract

Aim: This study aimed to investigate the incidence of relapse and FR/SDNS in Chinese children with SSNS and to develop clinical prediction models for relapse and FR/SDNS.

Methods: This retrospective cohort study involved 339 newly onset SSNS patients between 2006 and 2016. The incidence of relapse and FR/SDNS were estimated using the Kaplan-Meier method. Prediction models were constructed based on Cox proportional-hazards regression.

Results: The median follow-up time was 8.7 years. The cumulative incidence of relapse at 1-, 2-, and 5-year was 51.0%, 62.5%, and 66.6%. The cumulative incidence of FR/SDNS at 1-, 2-, and 5-year was 18.4%, 29.0%, and 32.9%. The final prediction model for first relapse included four variables (serum albumin, triglycerides, IgM, and time to first remission). The model's discriminative ability was low (Harrell's C index = 0.62). The final prediction model for FR/SDNS included four variables (serum albumin, lipoprotein(a), time to first remission, and time to first relapse). The discrimination and calibration of the prediction model for FR/SDNS were acceptable (Harrell's C index = 0.73, Brier score at 1- and 2-year were 0.11 and 0.17).

Conclusion: The first relapse and FR/SDNS mainly occurred in the first 2 years after initial SSNS onset. The prediction model for relapse developed using common clinical parameters performed poorly, while the prediction model for FR/SDNS might be useful.

Keywords: child; frequently relapsing nephrotic syndrome; relapse; steroid-dependent nephrotic syndrome; steroid-sensitive nephrotic syndrome.