Issue 173 Item 15 Triple Antihypertensive RX Urged for Diabetics

Combined treatment with an angiotensin-active drug, a diuretic, and a calcium channel blocker is a good blood pressure-lowering regimen for most patients with diabetes.

“For most patients with diabetes and hypertension, the first drug to use is an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker for their renal-protective effect, because nephropathy is a major problem in diabetes,” said Dr. Kaplan, a professor of medicine at the University of Texas Southwestern Medical Center, Dallas.

A diuretic is a good second-line agent to pair with an angiotensin-active drug, and for the many patients with diabetes who need a third drug to reach their goal blood pressure, a calcium channel blocker is a good third-line choice because this class has the most potent blood pressure lowering effect, he said.

Some physicians have become concerned about prescribing a calcium channel blocker for patients with diabetes and proteinuria because the results from the recent African American Study of Kidney Disease and Hypertension indicated that this class can worsen kidney damage in such patients, but this concern is unfounded, said Dr. Kaplan. In that trial, the calcium channel blocker amlodipine was given to patients who were not already on an angiotensin-active drug, noted Dr. Kaplan.

“Using a calcium channel blocker in the presence of an ACE inhibitor has never been shown harmful,” he said.

He specifically recommended that physicians prescribe a dihydropyridine calcium channel blocker, such as amlodipine, when combining an ACE inhibitor with a diuretic and a calcium channel blocker. “A nondihydropyridine drug may work even better, but none of these drugs have ever been assessed in patients with diabetes,” he told this newspaper.

Dr. Kaplan also stressed the importance of treating hypertension in patients with diabetes. He cited the findings reported last year from a study organized and sponsored by the Centers for Disease Control and Prevention that assessed the cost-effectiveness of various interventions in patients with diabetes. The results showed that intensive management of hypertension saved nearly $2,000 for every quality-adjusted life year gained, and that blood pressure control was far more cost-effective than either glycemic control or controlling serum lipid levels (JAMA 287[19]:2542-51, 2002).

Study results have also shown that the goal blood pressure for patients with diabetes should be less than 130/80 mm Hg. Although drug therapy is almost always needed to get patients with diabetes to this goal, lifestyle modification is also a key element, including weight loss, increased physical activity, reduced dietary sodium, maintenance of adequate calcium and magnesium in the diet, smoking cessation, and moderation of alcohol use.

Regular alcohol consumption is often proscribed for patients with diabetes because it’s considered to have “empty calories,” but according to Dr. Kaplan this is an overly extreme step. He cited the results from an epidemiologic study that included about 1,000 patients with diabetes. The results showed that among patients who said that they never used alcohol, the death rate was about 20% higher than that among patients who consumed about one to two drinks per day.

“I recommend that even patients with diabetes consume one to two drinks per day so that they have the cardioprotective effects of alcohol,” he said at the annual meeting of the Inter-American Society of Hypertension