The Treatment Response to Angiotensin Receptor Blocker According to ACE Gene Polymorphism in Patients with IgA Nephropathy

Park, Mina; Jeong, Kyung Hwan; Mon, Joo Young; Lee, Tae won; Ihm, Chun Gyoo; Lee, Sang Ho

Abstract

PURPOSE: Each and every patients therapeutic response to ACE inhibitor in IgA nephropathy can be different. The diversity may be caused by ACE polymorphism. The previous studies did not reveal the consistency of relation between ACE polymorphism and ACE inhibitor. We consider the incomplete blockade of ACE inhibitor for RAAS is the one of various reasons. We evaluated the relation between ACE polymorphism and ARB in IgA nephropathy.
METHODS
Among patients confirmed in IgA nephropathy and treated with ARB, 40 patients with over 0.5 g/day proteinuria and less 1.5 mg/dL serum creatinine were reviewed. Genomic DNA was extracted from blood and PCR was performed. Complete response was defined that proteinuria was less than 0.3 g/day after treatment. Partial response was defined that proteinuria was decreased over than 50%, but more than 0.3 g/day. Non-response was defined that proteinuria was decreased less than 50%.
RESULTS
The median follow-up duration was 6 months (95% Cl, 5.5-7.9). The serum creatinine was 1.2+/-0.6 mg/dL and median proteinuria was 1.6 g/day (95% Cl, 1.4-2.3). 15 complete responses, 11 partial responses and 14 non-responses were observed. The differences in the therapeutic response to ARB were observed according to ACE polymorphism (p=0.02). The response rate among each group was II:ID:DD=43%:68%:100% (p=0.03), and there was a significant difference in the therapeutic response to ARB between the DD/ID genotype and the II genotype (p=0.01).
CONCLUSION
In IgA nephropathy, there was a significant relation between the therapeutic response to ARB and the ACE polymorphism. Especially DD/ID genotype revealed better response to ARB than II genotype.