RESUMO
Angiotensin converting enzyme inhibitors (ACEI) are the most effective antiproteinuric agents and should be used as first-line drugs in both diabetic and non-diabetic proteinuric nephropathies. The role of calcium channel blockers (CCB) is much more controversial. In diabetic patients verapamil and diltiazem seem more effective than dihydropyridines in reducing urinary protein excretion, and have additive effects with ACEI, but little is available on chronic treatment of non-diabetic nephropathies for non-dihydropyridine CCBs. To test whether the combination of verapamil 180 mg or amlodipine 5 mg with trandolapril 2 mg reduces urinary protein excretion more than trandolapril 2 mg alone, we planned a prospective, randomized, double-blind, multicenter trial. The secondary aims are to evaluate the effects of both treatments on the selectivity of proteinuria and check their safety. Consecutive patients aged between 18 and 70 years with non-diabetic proteinuria > or =2 g/24 h and plasma creatinine < 3 mg/dl or creatinine clearance > or = 20 ml/min are asked to participate. After a four-week run-in during which previous antihypertensive therapy is withdrawn, a single dose of trandolapril 2 mg is given once a day in open conditions for four weeks. At the end of this period patients are randomly assigned to receive once a day, in a double blind fashion, either trandolapril 2 mg and verapamil 180 mg [plus a placebo], or trandolapril 2 mg plus amlodipine 5 mg. They are monitored after one, two, five and eight months.
