Analysis of prognostic factors for patients with IgA nephropathy and establishment of a nomogram prediction model

Objective To explore the prognostic factors for patients with IgA nephropathy （IgAN）and establish a nomogram model for predicting short-term prognosis. Methods From July 1， 2018 to October 1，2021，254 patients with an initial diagnosis of IgAN by renal biopsy were selected as research subjects. The relevant clinical data were collected during a follow-up period of at least 3 months. The study endpoint was a 24-hour urinary protein quantity of≤0.3 g or a 24-hour urinary protein quantity of >0.3 g with a decrease of≥50% from baseline. Both univariate and multivariate Cox regression analyses were performed. And stepwise regression method was employed for examining the influencing factors of the prognosis of IgAN and nomogram model constructed. Concordance index and calibration curve were employed for evaluating the discriminativeness and accuracy of model and receiver operating characteristic（ROC）curve plotted for evaluating the capability of nomogram model in predicting the prognosis. Results 24-hour urinary protein quantification（HR=0.716，95%CI： 0.599-0.856），use of immunosuppressants（HR=0.154，95%CI： 0.443-0.931）and degree of renal tubular atrophy/interstitial fibrosis（HR=0.153，95%CI： 0.047-0.497）was independent predictors of short-term 24-hour urinary protein remission. The agreement index of prediction model was 0.730（95%CI： 0.683-0.777）and the area under the ROC curve（AUC）0.886（95%CI： 0.839-0.923）. Conclusion 24-hour urinary protein quantification，use of immunosuppressants and degree of renal tubular atrophy/interstitial fibrosis are independent predictors of 1/3-year urinary protein remission in IgAN patients.