Supportive Management of IgA Nephropathy With Renin-Angiotensin Blockade, the AIIMS Primary IgA Nephropathy Cohort (APPROACH) Study

Introduction: Renin-angiotensin system (RAS) blockade using angiotensin-converting enzyme inhibitor (ACEi)/angiotensin receptor blocker (ARB) is first-line therapy for IgA nephropathy (IgAN). There is a paucity of information on the predictors and magnitude of response to this treatment. Methods: In a prospective study, treatment-naive patients with IgAN with urinary protein >= 1 g/d and estimated glomerular filtration rate (eGFR) >= 30 ml/min per 1.73 m(2) received supportive treatment including ACEi (ramipril) or ARB (losartan) in patients intolerant to ACEi, and optimal blood pressure (BP) control to <= 130/80 mm Hg, with a follow-up of 6 months. The primary outcome was remission of proteinuria. Complete remission (CR) was defined as proteinuria < 0.5 g/d and partial remission (PR) as proteinuria < 1g/d with at least a 50% decline from the baseline with stable renal function (<= 25% reduction in eGFR). Results: A total of 96 patients were analyzed, with a mean age of 33.3 +/- 10.2 years, baseline eGFR 74.0 +/- 30.9 ml/min per 1.73 m(2), and urinary protein 2.6 +/- 1.2 g/d. In all, 71.9% patients received >= 75% of the maximum approved dose of ACEi/ARB. Remission was observed in 36.5% (CR, 6.3%) patients at 3 months and in 55.2% (CR, 31.3%) at 6 months. Patients who failed to achieve remission had lower baseline eGFR (P = 0.002) and serum albumin levels (P< 0.001), asymptomatic hyperuricemia (P < 0.001), and higher proteinuria (P = 0.076). E1 (P= 0.053) and T1/T2 (P = 0.009) lesions were more frequent on histology. The ACEi/ARB had to be discontinued in 17 (17.7%) patients. These patients were older (P= 0.085) with lower eGFR (P < 0.002) and serum albumin levels (P = 0.001) and more E1 (P = 0.012) and T1/T2 (P = 0.001) lesions on histology. Conclusion: Meticulous supportive therapy with optimal use of ACEi/ARB achieved remission in half of IgAN patients in this study. Increasing the treatment duration to 6 months improved remission rates. Patients with severe clinical and histological disease were less likely to tolerate and respond to treatment with RAS blockade.

Automated summary

This study demonstrates that half of IgA nephropathy patients achieved remission after 6 months of ACEi/ARB treatment. Patients who were older, had lower eGFR, and showed worse histological presentations were less likely to tolerate and respond to the treatment.