High-Dose ARB Decreases Proteinuria
At 30 weeks, even diabetics had a 33% reduction, researchers report.
LONDON, Ont.—High doses of the angiotensin receptor blocker (ARB) candesartan reduce proteinuria by one third, even in people with diabetes, according to a study.
At the Canadian Society of Nephrology's annual meeting here, researchers presented findings showing that 30 weeks of treatment with candesartan 128 mg/day—four to eight times the dose usually used to treat hypertension—was associated with a 33% decrease in proteinuria.
“I would not recommend this approach outside of specialists' hands,” said lead investigator Norman Muirhead, MD, of the University of Western Ontario in London, Ont., Canada. “Care also needs to be taken to ensure patients have their serum potassium controlled prior to initiating high-dose ARBs, and I would not recommend this approach in patients with ad-vanced kidney failure.”
His team's study, dubbed SMART (Supra Maximal Atacand Renal Trial), involved 29 academic and community nephrology centers in Canada. AstraZeneca funded the study. Ninety patients with proteinuria were randomized to candesartan 16 mg/day—the recommended dose for hypertension—another 90 to candesartan 64 mg/day, and 89 to candesartan 128 mg/day.
After six and 30 weeks, patients receiving either 64 or 128 mg/day had much greater reductions in proteinuria than did those receiving doses of 16 mg/day, peaking at a 33% reduction at 30 weeks in the highest-dose group. The only group to show an association between reduction in systolic BP and reduction in proteinuria were those with baseline proteinuria of 3 g/day or less randomized to candesartan 128 mg/day, the study found. The robust proteinuria-reducing effect was present in people with or without diabetes.