The effect of beta-blockade and angiotensin converting enzyme inhibition on kidney function in diabetic nephropathy.

Diabetic nephropathy is characterized by persistent albuminuria, a decline in glomerular filtration rate (GFR) and elevated blood pressure. About 40% of all insulin-dependent diabetic patients will develop nephropathy, thus increasing their morbidity and mortality. The effect of early aggressive antihypertensive treatment with metoprolol, frusemide or thiazide in insulin-dependent diabetic patients with nephropathy has shown a significant reduction in albuminuria and in the rate of decline in the GFR (from 0.94 to 0.29 and 0.10 ml/min per month over 72 months of antihypertensive treatment). The effect of angiotensin converting enzyme (ACE) inhibition on kidney function in diabetic nephropathy showed that the GFR is not dependent on angiotensin II (Ang II), and that ACE inhibition diminished albuminuria, probably by lowering glomerular hypertension. In conclusion, antihypertensive treatment with ACE inhibitors or beta-blockers combined with a diuretic protects kidney function and reduces albuminuria in diabetic nephropathy. Angiotensin converting enzyme inhibitors can be considered as first-line drugs for hypertensive patients with diabetic nephropathy.