Renal Protection in Diabetes-An Emerging Role for Calcium Antagonists

The combination of diabetes and hypertension increases the chances of progressive renal disorder and ultimately renal failure. Roughly 40% of all diabetics, whether insulin dependent or not, develop diabetic nephropathy. Diabetic nephropathy is the single most important cause of end-stage renal disease in the western world and accounts for more than a quarter of all end-stage renal diseases. It is also a major cause of increased morbidity and mortality in diabetic patients. Increased arterial blood pressure is an early and common phenomenon in incipient and overt diabetic nephropathy. The relationship between arterial blood pressure and diabetic nephropathy is a complex one, diabetic nephropathy increasing blood pressure and blood pressure accelerating the course of nephropathy. Calcium antagonists antagonize preglomerular vasoconstriction. Furthermore, additional putative mechanisms include the ability to retard renal growth and possibly to attenuate mesangial entrapment of macromolecules and to attenuate the mitogenic effects of diverse growth factors. Calcium antagonists (except the old short-acting dihydropyridine drugs) reduce microalbuminuria and preserve kidney function in d