Optimizing therapy in the diabetic patient with renal disease: antihypertensive treatment

Hypertension, impaired renal function, and proteinuria are commonly associated to the presence of diabetes. They play a major role in the development of cardiovascular and renal damage. Effective antihypertensive treatment reduces the progression of diabetic nephropathy and improves cardiovascular prognosis. Accordingly, tight BP control (<130/80 mmHg) is currently recommended in diabetic patients. Achieving BP targets represents the most important determinant of cardiovascular and renal protection. However, it has been suggested that specific classes of antihypertensive drugs may exert additional organ protection beyond their BP control. The pharmacologic blockade of the renin-angiotensin-aldosterone system has been shown to convey greater renal and cardiovascular protection compared with other classes of drugs. In particular, studies focusing on renal end point suggest that angiotensin-converting enzyme inhibitors (ACEI) are the first-choice drugs in type 1 diabetes. Both ACEI and angiotensin II receptor blockers prevent the progression from microalbuminuria to clinical proteinuria in type 2 diabetes, but angiotensin blockers provide better renoprotection in patients with overt nephropathy. Regarding cardiovascular protection, several studies (but not all) have shown that ACEI exert a protective effect on diabetic patients. Recently, interesting results in favor of angiotensin receptor blockers have been reported in the IDNT, RENAAL, and LIFE studies. It should be noted that to achieve maximal renal and cardiovascular protection, most diabetic patients require integrated therapeutic intervention, including not only several antihypertensive drugs, but statins and antiplatelet therapy as well.