In contrast, ACE inhibitors overused for hypertension

Diuretics, beta-blockers should be first-line Rx

If you're working on increasing the number of patients in your program who receive ACE inhibitors, make sure you're concentrating on patients with congestive heart failure. A new study1 shows that ACE inhibitors are being prescribed too often for patients with uncomplicated hypertension. This is also true for calcium channel blockers (CCBs), which can actually have negative effects on the heart.

And considering that 50 million Americans have hypertension and that CCBs, for example, cost nearly 100 times more than diuretics, following the guidelines could potentially save hundreds of millions of dollars, Siegel says.

"It's unproven that ACE inhibitors and CCBs have the same beneficial effects in hypertension as beta-blockers and diuretics," says David Siegel, MD, MPH, chief of medicine for the Veterans Affairs Northern California Health Care System, based in Martinez, CA, and lead author of the study. "Clearly, diuretics and beta-blockers have a proven benefit against stroke, progression to heart failure, mortality, coronary artery disease, and so on. ACE inhibitors are certainly good drugs, especially with congestive heart failure and diabetes, but in terms of hypertension, they're not the first choice."

Researchers looked at all prescriptions dispensed at 35,000 pharmacies nationwide (62% of all U.S. retail pharmacies) in 1992 and 1995 to determine prescribing patterns for antihypertensive medications. They found that use of calcium channel blockers and ACE inhibitors increased, while diuretics and beta-blockers decreased in those three years. Calcium channel blockers went from 33% of antihypertensive prescriptions in 1992 to 38% in 1995, ACE inhibitor use went from 25% to 33%, beta-blocker use from 18% to 11%, and diuretic use from 16% to 8%.

Siegel concluded that the Fifth Joint National Committee on the Detection, Evaluation, and Treatment of High Blood Pressure (JNC V) guideline that was released in 1993 had little effect on prescribing patterns. JNC V diverged from JNC IV, published in 1988, by recommending diuretics and beta-blockers as first-choice agents over calcium channel blockers and ACE inhibitors because of their proven benefits in reducing morbidity and mortality and their lower cost.

Why are physicians ignoring the guidelines? "There are some concerns that diuretics and beta-blockers have more side effects, but I happen to think that's not true," Siegel says. "I also think ACE inhibitors and calcium channel blockers are promoted a lot by pharmaceutical companies, and there may be some feeling that newer is better. But the motivation of people in their prescribing patterns has not been well studied." Other possible problems are the need to individualize drug treatment when other conditions are present and the failure to disseminate the recommendations.

JNC VI, the most recent guideline published in November, may take care of some of the comorbidity confusion by recommending individualized drug therapy based on specific conditions. For example, elderly patients with isolated systolic hypertension should first be treated with diuretics. Patients with diabetes, kidney damage, and hypertension should receive ACE inhibitors. Heart attack patients with hypertension should get beta-blockers and, in some cases, ACE inhibitors.

[For more information, contact David Siegel, MD, MPH, Department of Veterans Affairs NCHCS, 150 Muir Road, Martinez, CA 94553. Telephone: (510) 372-2076.]

Reference

1. Siegel,, "Trends in Antihypertensive Drug Use in the United States," JAMA 1997; 278:1,745-1,748.