Combined Immunosuppressive Treatment May Improve Short-Term Renal Outcomes in Chinese Patients with Advanced IgA Nephropathy

Abstract

Background/Aims: Treatment of advanced Immunoglobulin A nephropathy (IgAN) patients with estimated glomerular filtration rate (eGFR) below 45 mL/min per 1.73 m2 remains inconsistent. The aim of this study is to compare the effects of corticosteroid and immunosuppressant therapies among these patients. Methods: A total of 201 adult patients with advanced IgAN (eGFR < 45 mL/min/1.73 m2 and proteinuria > 1 g/24h at biopsy) grouped into supportive care (SC), steroids alone (CS), and steroids plus immunosuppressant (IT) groups, were investigated between 30th December 2002 and 30th June 2016. The primary endpoint was the combined endpoint of a 50% decline in eGFR and/or end stage renal disease (ESRD: eGFR < 15 mL/min/1.73 m2 or maintenance renal replacement treatment). Responses to therapy included complete remission (CR: urinary protein excretion < 0.5 g/24h, with eGFR decrease less than 10% baseline), partial remission (PR: proteinuria decrease by > 50% baseline, with eGFR decrease less than 10% baseline), no response (NR: proteinuria decrease < 50% baseline, or eGFR decrease > 10% baseline) and ESRD. Kaplan–Meier and Cox proportional hazards analyses were performed. Results: During the follow-up period (37.2 ± 22.7 months), 6.8% patients in SC group, 25.0% in CS group, and 38.0% in IT group achieved CR or PR, while 78.4%, 62.5% and 49.3% patients in these 3 groups reached primary endpoint respectively (p < 0.001). Three-year renal survival rates in SC and combined immunosuppressive treatment groups (CS and IT groups) were 33.8% vs 51.2% (p = 0.02), and 5-year renal survival rates were 12.2% vs 21.3% (p = 0.1) respectively. Multivariate Cox regression analysis showed that hypertension (HR = 2.44, 95% CI 1.51–3.95; p < 0.001), Scr (HR = 1.01, 95% CI 1.00-1.01; p < 0.001), T1-T2 lesion (HR = 1.99, 95% CI 1.35–2.93; p = 0.001) were independent indicators of poor renal outcome. Conclusion: Immunosuppressive treatment (CS and IT therapy) may improve short-term renal outcome compared with supportive treatment in advanced IgAN patients.