Diabetics Get Kidney Protection From ARBs
This is a significant issue because diabetes and high blood pressure are both separate risk factors for heart disease and stroke. A patient with both faces double jeopardy. But another class of high blood pressure medications, called angiotensin-converting enzyme inhibitors, or ACE inhibitors, can protect the kidneys and reduce the risk of death from heart disease. Until the release of these new ARB studies, ACE inhibitors have been considered the drug of choice for treating high blood pressure in diabetics. Importantly, none of the studies presented Saturday compared the ARBs against an ACE inhibitor, so it's unknown whether ARBs also can reduce the risk of death from heart disease.
Bakris was an investigator in Brenner's study, and he acknowledges that the study was not designed to evaluate whether Cozaar reduces the risk of heart disease. However, he tells WebMD that Cozaar did reduce "hospitalization for heart failure by 32%."
Parving, who studied nearly 600 people with patients with the earliest stage of kidney disease -- a condition called microalbuminuria -- says that in his study when patients were given Avapro, they had about half the number of heart attacks and strokes as patients who were treated with other blood pressure drugs.
Microalbuminuria means that very small amounts of albumin can be detected in the urine. Brenner says that microalbuminuria happens when "blood vessels in the kidney start leaking protein, which means the vessels are damaged." Parving's study evaluated whether Avapro prevented or slowed the progression of kidney disease from this very early stage. Avapro reduced the risk of progression by 10%, he tells WebMD.
One advantage that the ARBs have over ACE inhibitors is that these drugs are more patient friendly, notes Brenner, who says about one in five patients will stop taking an ACE inhibitor because the drug often causes a dry, hacking cough. There is no cough associated with ARBs, he says.
But the downside of ARBs is cost. Sometimes both an ARB and an ACE-inhibitor fail to control blood pressure without the help of other drugs. Typically patients will take two or more blood pressure medicines, says Bakris. "That means an ACE [inhibitor] or an ARB plus other drugs -- sometimes several other drugs," he says.
ARBs cost about 15-25% more than an ACE inhibitor, especially since generic versions of some ACE inhibitors are available. Since many type 2 diabetics are covered by Medicare, which doesn't pay for prescription drugs, the price of adding an expensive drug to an already long list of medications can create a hardship, says Bakris.