Impact of crescents on the immunosuppression treatment of IgA nephropathy

Crescents are a histopathological feature of the kidney and are associated with poor renal outcomes in patients with IgA nephropathy. The efficacy of immuno­suppressive therapy for IgA nephropathy patients presenting with crescents is still debated. A total of 1,394 patients were diagnosed with IgA nephropathy with crescents confirmed by renal biopsy between April 2017 and November 2021. The cohort comprised 391 patients receiving immunosuppressive therapy and 391 propensity score-matched patients managed with supportive care. The primary composite outcome included:≥40% eGFR decline from baseline, annual eGFR decline rate >5 mL/min/1.73 m², kidney replacement therapy, or all-cause mortality. A Cox proportional hazards model was employed to evaluate the associations between immunosuppression and composite outcomes, including their individual components, in both the propensity score-matched cohort as well as in the IgA nephropathy with crescents cohort. Among the 782 individuals, 74 reached the composite outcome, 28 in the immunosuppression group and 46 in the supportive care group. Immunosuppressive therapy was associated with a 39% lower risk of the composite outcome (aHR 0.61; 95% CI, 0.38–0.98). In subgroup analyses of the propensity score-matched cohort, immunosuppressive therapy was associated with a reduced risk of the composite outcome after adjustment for the Oxford classification (M, E, S, T) in IgA nephropathy patients with C1. Immunosuppressive therapy was associated with a 39% lower risk of the composite outcome, demonstrating consistent efficacy in IgA nephropathy with C1.