Long-term renal prognosis of IgA nephropathy with therapeutic trend shifts

Abstract

Objective: We compared the effect of treatments in the long-term renal survival of IgA nephropathy. Methods: One hundred and fourteen patients with biopsy-proven IgA nephropathy were retrospectively divided into 4 groups, reflecting shifts in treatment trends from 1985 to 2005: patients without treatment (no treatment group; n=36), patients treated only with anti-platelet drugs (anti-platelet group; n=12), those treated mainly with angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) (ACEI/ARB group; n =29), and prednisolone-treated patients (PSL group; n =37). Results: Baseline blood pressure, serum creatinine and renal histological findings were similar among the 4 groups; however, the urinary protein level was significantly severer in the PSL group. After a mean follow-up of 7.0±0.5 years, end-stage renal disease occurred in 11 patients (31%) in the no treatment group, 5 patients (42%) in the anti-platelet group and 3 patients (8%) in the PSL group, but in only 1 patient (3%) in the ACEI/ARB group. Kaplan-Meier renal survival after 20 years was significantly better in the ACEI/ARB group than in the anti-platelet group or in the no treatment group (p<0.05). The patients that reached complete remission (CR) by steroid therapy showed less baseline urinary protein and milder histological lesions than those who did not reach CR. The non-CR group showed increases in serum creatinine and eGFR reduction rate. Conclusion: Treatment with renin-angiotensin system inhibitors showed the greatest improvement of 20-year renal survival in IgA nephropathy patients. Steroid therapy achieved complete remission in some early-stage cases. © 2009 The Japanese Society of Internal Medicine.