Blood Pressure Control and Nephroprotection in Diabetes

Achievement of recommended levels of blood pressure as prescribed by guidelines (i.e., systolic blood pressure of < 130 mmHg in people with nephropathy secondary to type 2 diabetes) generally requires three or more different antihypertensive agents that have complementary modes of action. This systolic goal blood pressure, recommended by generally all international guideline committees, was derived from largely observational studies demonstrating a greater reduction of cardiovascular risk and preservation of kidney function at these levels. Commonly used antihypertensive combinations include angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers, which have compelling indications for use in people with kidney disease and/or diabetes, combined with a diuretic, generally a thiazide-type agent. If additional therapy is required, either a beta-blocker or a calcium antagonist may be added to this antihypertensive "cocktail." Beta-blockers are particularly effective in people with a high sympathetic drive (i.e., high pulse rates) to lower blood pressure and reduce cardiovascular risk. Moreover, in recent studies, their benefits on kidney function, both by reducing macroalbuminuria and slowing the decline of kidney function, make them good agents to add in the appropriate clinical setting. With all these potential benefits of achieving blood pressure goals, it is unfortunate that only 11% of people being treated for hypertension with diabetic kidney disease achieve the blood pressure goal of < 130 mmHg, likely contributing to the climbing incidence of people starting dialysis. Physicians need to work harder and educate patients on the importance of achieving these lower blood pressure guidelines.