Hypertension and diabetes: the scope of the problem

Cardiovascular and renal diseases in diabetes stem from an accelerated form of atherosclerosis in both small and large blood vessels. Diabetic nephropathy is a clinical hallmark of microangiopathy and often leads to end-stage renal failure. Significantly, microalbuminuria is an independent predictor of cardiovascular morbidity and mortality in both the diabetic and non-diabetic population. In diabetic patients, it is also strongly associated with proliferative retinopathy, neuropathy and hypertension. Effective blood pressure reduction in patients with type 2 diabetes and diabetic nephropathy is known to reduce albuminuria, delay the progression of diabetic nephropathy, postpone renal failure and improve survival. These benefits have been demonstrated with a variety of blood pressure-lowering agents, including beta-blockers, calcium channel blockers, diuretics and angiotensin-converting enzyme (ACE) inhibitors. Less is known about the renal effects of the newest class of antihypertensive agents, the angiotensin II receptor antagonists (AIIRAs). Irbesartan is an AIIRA that provides antihypertensive efficacy comparable to ACE inhibitors but with superior tolerability. The PRogram for Irbesartan Mortality and morbidity Evaluations (PRIME) is an important morbidity and mortality program encompassing the Irbesartan Diabetic Nephropathy Trial (IDNT) and the IRbesartan MicroAlbuminuria type 2 diabetes mellitus in hypertensive patients (IRMA II) study. PRIME is evaluating the effects of irbesartan in preventing diabetic nephropathy and end-stage renal failure and in reducing cardiovascular events in high-risk hypertensive patients with type 2 diabetes. The trials were completed at the end of 2000.