ACE INHIBITORS: WHAT AND WHY

by Peter J. Nebergall, PhD

A significant percentage of diabetics will develop measurable nephropathy, kidney disease. Statistics suggest up to half of these people may progress to ESRD, end stage renal disease. So are you doomed?

No. First remember statistics measure the past, not the future, and medicine is getting better all the time. The outlook is MUCH better today than it was 20, 10, or even five years ago. Second, we have new tools proven to slow, maybe even halt, the progression from kidney disease into kidney failure.

The Angiotensin-Converting Enzyme ("ACE") Inhibitors are not new; they have been used for some time as a treatment for hypertension, high blood pressure. And they work. Doctors noticed that, for diabetics, they work especially well.

In 1993, a major study proved ACE Inhibitor Captopril, a common blood pressure medication, significantly reduced diabetic kidney degeneration. Based on these findings, the U.S. Food and Drug Administration has recommended use of Captopril for patients with early signs of kidney damage.

Doctors now prescribe many ACE Inhibitors, Lisinopril, Accupril, Ramipril, and others, to reduce fluid pressure on damaged kidneys and slow the progression of diabetic kidney disease. While the relationship between high blood pressure and diabetogenic kidney damage is obvious (cut the pressure--cut the damage), the kidneys have "pressure" of their own, and some doctors are prescribing ACE Inhibitors, to cut the kidney's internal fluid pressure, even where the diabetic's blood pressure is not measurably elevated. Small doses of the medication appear effective against diabetic kidney disease even when the blood pressure is "normal."

Of course you and your doctor need to proceed with caution, if you choose that route. Not because the drug is dangerous ("There are no contraindications for Ramipril or any ACE Inhibitors, in general, for persons with diabetes," says Arturo Rolla, MD, of Harvard Medical School), but because too high a dose can lead to the woozy symptoms of low blood pressure.

New research suggests further benefits from the ACE Inhibitors. A major Canadian study of Ramipril (trade name Altace), not limited to diabetics, showed the drug reduced heart attacks by 20% and strokes by 31% (in a test population of individuals with high blood pressure), but it also showed a significant reduction in outbreak of type 2 diabetes (in the test population), compared with a control group of similar individuals not receiving the medication. This last finding was not expected, and will require further study.

But the message is clear: If you have diabetes, and are beginning to show signs of kidney disease (microalbuminuria), regular therapy with the ACE Inhibitors can cut the progression of kidney disease, reduce the risk of heart attack and stroke, and may reduce risk of neuropathy and retinopathy as well.

And that's good news for the new year.