Background: The impact of renin-angiotensin system blockade (RASB) on the incidence of end-stage renal disease (ESRD) remains unclear in IgA nephropathy (IgAN).
Methods: This study assessed associations between RASB treatment and the incidence of ESRD in IgAN using propensity score approaches. We retrospectively analyzed 1273 patients with IgAN biopsied between 1979 and 2010. Propensity scores were calculated using logistic regression. Associations between RASB and ESRD were examined using a Cox regression model adjusted by inverse probability of treatment weighted, regression, stratification and matching.
Results: During follow-up (median 5.1 years), 130 patients developed ESRD. With Cox regression adjusted by inverse probability of treatment weighted, RASB use was significantly associated with a lower risk of ESRD (hazard ratio 0.58; 95 % confidence interval 0.42-0.80). Significant associations were observed for other propensity score-based approaches. In stratified analysis, a beneficial association between RASB and ESRD was observed in patients ≥35 years, with hypertension, reduced estimated glomerular filtration rate (<60 mL/min/1.73 m2), mesangial proliferation and segmental glomerulosclerosis (P for interaction <0.05), and tended to be greater in patients with proteinuria (≥1.0 g/24 h), extracapillary proliferation and receiving methylprednisolone pulse therapy (P for interaction <0.10).
Conclusion: Treatment with RASB was associated with a lower incidence of ESRD in the real-world practice of IgAN.
Keywords: Causal effect; Interaction; Pathology.