Diuretics Best for High Blood Pressure
Cheaper Drugs Are More Effective at Preventing Stroke, Heart Failure
The findings could have major implications for the newer drugs and their manufacturers. The new drugs have taken a significant chunk of the high blood pressure drug market.
According to the researchers, diuretics fell from 56% of prescriptions for high blood pressure in 1982 to 27% in 1992, giving way to the newer drugs. They estimate that sticking with diuretics would have saved more than $3 billion. About 24 million Americans take drugs to lower high blood pressure, costing about $15.5 billion annually. To put it more succinctly: Switching from newer drugs to a diuretic would save between $250 and $650 per patient per year, the researchers say.
The blood pressure study included more than 42,000 participants aged 55 and older. They received either the diuretic chlorthalidone or one of the new blood pressure drugs -- Norvasc (a calcium channel blocker) or Prinivil or Zestril (generic name lisinopril -- an ACE inhibitor). The part of the study that looked at Cardura -- an alpha adrenergic blocker -- was stopped in 2000 because of an increase in heart disease and stroke among study participants.
In the study, the researchers were mainly looking for how well each blood pressure drug prevented a heart attack or death from heart disease. In addition, they looked for other complications of high blood pressure -- including stroke and heart failure.
After five years, researchers found that the diuretic was just as good at preventing heart attack or death as the newer drugs. But the medicines had different effects on blood pressure. The diuretic was better at lowering systolic blood pressure -- the top number -- than the newer drugs, but Norvasc was better at lowering diastolic blood pressure -- the bottom number.
For heart failure, people taking Norvasc had a 38% higher risk of developing heart failure and a 35% higher chance of being hospitalized for the condition. Those on the ACE inhibitor had a 15% higher risk of stroke, a 19% higher risk of developing heart failure, and other increased risks compared with people taking a diuretic.
Even though the overall death rate was about the same in all groups, strokes and heart attacks seriously reduce quality of life. "These have major impacts on people's lives," said Barry R. Davis, MD, PhD, professor of biometry at the University of Texas School of Public Health and the lead investigator on ALLHAT.