The combination of drugs traditionally used to control blood pressure might not be ideal for Hispanic patients, University of Florida researchers warn.
While beta-blockers and diuretics have long been used to treat patients with hypertension, Hispanic patients appear to benefit from a tailor-made strategy that includes other medications, particularly calcium antagonists and angiotensin-converting, or ACE, inhibitors.
Not only does the approach effectively lower blood pressure in many Hispanic patients, it has an extra benefit: It dramatically cuts their risk of developing diabetes. UF researchers reported the findings in this month's issue of the American Heart Journal.
"We can successfully lower blood pressure in Hispanic patients with heart disease with medications that include beta-blockers like atenolol or calcium antagonists like verapamil plus the ACE inhibitor trandolapril, especially when compared with non-Hispanic patients," said Rhonda Cooper-DeHoff, Pharm.D., a research assistant professor and associate director of the clinical research program in cardiovascular medicine at UF's College of Medicine. "Lower blood pressure translated into fewer heart attacks and fewer strokes, which is very important for reducing cardiovascular risk in both Hispanics and non-Hispanics.
"The use of trandolapril and verapamil, however, also significantly reduced the risk of developing diabetes in Hispanic patients," she said.
Researchers involved in the landmark International Verapamil SR-Trandolapril study, known as INVEST, were intrigued by the finding in part because patients with high blood pressure and cardiovascular disease - in particular those of Hispanic descent, the fastest-growing ethnic minority in the United States - are much more likely to develop diabetes. Those who do are twice as likely to suffer serious complications associated with heart disease.
UF researchers tracked more than 22,500 patients from 14 countries - including about 8,000 Hispanics - for two to five years. The study enrolled more Hispanic patients than any other hypertension trial to date, Cooper-DeHoff said, and included Hispanic participants from the mainland United States, Puerto Rico, Cuba, Mexico, Canada, Guatemala, Panama and El Salvador.
Participants were randomly assigned to receive a sustained-release form of the calcium antagonist verapamil or the beta-blocker atenolol. Both groups also could receive the ACE inhibitor trandolapril and the diuretic hydrochlorothiazide.
Researchers found that both treatment strategies controlled high blood pressure exceptionally well, safely lowering it below 140/90 in 72 percent of INVEST participants, who were mostly elderly. On average, it took at least two medications to lower blood pressure in Hispanic patients, compared with three in non-Hispanic patients.
Overall, Hispanic patients had a 19 percent increased risk of developing diabetes during the study's follow-up period, but those in the verapamil group were actually 15 percent less likely to develop diabetes, and the addition of trandolapril to verapamil was linked to the decreased risk.