Fig. 1

Survival curves for primary outcomes a in all IMN patients (n = 439): primary outcome-free time: 38.73 ± 19.35 months; b Solid lines: eGFR-EPI < 60 ml/min*1.73 m², dashed lines: eGFR-EPI ≥ 60 ml/min*1.73 m². In patients with eGFR-EPI ≥ 60 ml/min*1.73 m² vs eGFR-EPI < 60 ml/min*1.73 m²: primary outcome-free time: 39.13 ± 19.22 months vs 34.85 ± 20.36 months, P = 0.18; HR: 0.12(0.06–0.23), P < 0.01; c Solid lines: urine protein ≥ 4 g/24 h, dashed lines: urine protein < 4 g/24 h. In patients with urine protein < 4 g/24 h vs urine protein ≥ 4 g/24 h: primary outcome-free time: 42.14 ± 19.37 months vs 35.04 ± 18.67 months, P < 0.01; HR: 3.89(1.18–12.79), P = 0.03; HR: 2.35(1.19–4.65), P = 0.01. d Solid lines: ≥ 65 years, dashed lines: < 65 years. In patients aged < 65 years vs ≥ 65 years: primary outcome-free time: months 39.24 ± 19.17 vs 37.04 ± 19.90 months, P = 0.32; HR: 6.15(3.12–12.14), P < 0.01; Upro urine protein