CHICAGO (AP) _ An old-fashioned diuretic is as good, if not better, than some newer, more expensive medicines for treating high blood pressure and preventing its complications, according to a government-sponsored study released Tuesday.
Researchers suggest diuretics, commonly called water pills, should be the first medicine prescribed to treat high blood pressure and that, when multiple medications are needed, a diuretic be one of them.
Diuretics, which work by ridding the body of excess sodium and water, have long been used as a standard blood pressure medicine.
``The hope is that we make it easier for both providers and patients to achieve blood pressure control using the most effective, as well as least costly, medication,'' said Dr. Jackson T. Wright Jr. of Case Western Reserve University and vice chairman of the study's steering committee.
The study was mostly funded by the National Heart, Lung, and Blood Institute.
About 50 million Americans _ one in four adults _ are estimated to have high blood pressure, a risk factor for stroke and heart attack.
The eight-year study published in Wednesday's Journal of the American Medical Association looked at 33,357 patients age 55 and older from 623 sites in the United States, Canada, Puerto Rico and the U.S. Virgin Islands.
The study compared the generic diuretic chlorthalidone with two newer, more expensive blood pressure treatments, the ACE inhibitor lisinopril and the calcium channel blocker amlodipine.
The findings show a slightly greater percentage of patients got their blood pressure below 140/90, which was the goal of the study, when they used the diuretic compared to the two newer medicines.
Researchers also found the diuretic was better than the calcium channel blocker in preventing heart failure and better than the ACE inhibitor in preventing stroke, heart failure and chest pains.
While diuretics have long been used to treat high blood pressure, their use fell from 56 percent of all blood pressure prescriptions in 1982 to 27 percent in 1992, according to the researchers' Web site. Meanwhile, ``despite their increased cost and lack of proven superiority'' over older drugs, use of the newer drugs _ especially calcium channel blockers and ACE inhibitors _ has increased dramatically in the past decade, the Web site said.
The researchers say that diuretics are up 30 times cheaper than some of the newer medicines.
A third blood pressure drug, the alpha blocker doxazosin, was dropped from the study more than two years ago because it proved significantly less effective than diuretic treatment.
Diuretics might be excellent therapy for some, but not all patients can take them, noted Dr. David A. Meyerson, a Johns Hopkins University cardiologist and American Heart Association spokesman who was not involved in the research.
The study was part of a clinical trial that also looked at cholesterol-lowering in patients with high blood pressure. The cholesterol study covered 10,355 patients from the more than 42,000 people recruited for the blood pressure study.
In the second study, also sponsored by the government institute, the cholesterol-lowering drug pravastatin was compared to usual care given to patients, which typically meant a low-cholesterol diet.
However, as the study progressed, more patients in the usual care group began taking the cholesterol-lowering medications, called statins, because their conditions warranted it.
Those taking pravastatin reduced total cholesterol by 20 percent after six years, while the usual care group saw total cholesterol decline 11 percent. But the difference between groups might have been greater had some of the usual-care patients not started taking statins, said Dr. Barry R. Davis of the University of Texas School of Public Health in Houston and director of the study's clinical trials center.
Other research has shown that statins, specifically pravastatin, can reduce deaths from heart disease. When diet and lifestyle changes don't work in lowering cholesterol, patients should consider going on a statin drug to reduce their cholesterol, Davis said.