Angiotensin antagonists and fish oil for treating IgA nephropathy

Abstract

In IgA nephropathy (IgAN), ACE inhibitors (ACE-I) and angiotensin receptor blockers (ARB) are beneficial against hypertension, and their anti-proteinuric effect has been clearly demonstrated. However, sub-analyses of IgAN patients enrolled in large studies failed to prove a benefit against progression to renal failure. The European Community Biomed Concerted Action - a placebo-controlled randomized controlled trial begun in 1995 - in children and adults (9-35 years old) with proteinuria > 1 < 3.5 g/day/1.73 m(2) and normal or moderately reduced renal function proved the significant benefit of ACE-I on progression of kidney disease. The combination of ACE-I and ARB in proteinuric normotensive IgAN patients showed greater antiproteinuric effect and the COOPERATE trial also reported a superior effect of combination therapy in protecting against renal function deterioration. Treating IgAN with fish oil has a good rationale for renal inflammation as well as for prevention of cardiovascular morbidity. However, the published reports gave conflicting conclusions and also very recent data did not show significant benefits. In conclusion, ACE-I and ARB have a definite role in treating IgAN, particularly the hypertensive and proteinuric forms. These patients should be treated to target BP to <130/70 mm Hg and proteinuria <0.5 g/day.