Treatment with a low-dose diuretic cuts by half the chance that an older person with high systolic blood pressure will develop heart failure, according to results from a National Institutes of Health (NIH) trial. Those who had already had a heart attack experienced an even greater benefit--their chance of developing heart failure dropped by 80 percent.
The findings come from the Systolic Hypertension in the Elderly Program (SHEP), a long-term, multi-center trial supported by the National Heart, Lung, and Blood Institute (NHLBI) and the National Institute on Aging (NIA), both units of the NIH. The findings appear in the July 16, 1997, issue of the Journal of the American Medical Association.
"Heart failure has been increasing in the United States in recent years, the only cardiovascular disorder to do so," said NHLBI Director Dr. Claude Lenfant. "There are now about 400,000 new cases annually."
"These findings show that this alarming trend can be reversed," he continued. "Treating hypertension prevents heart failure, even for those with severe heart disease."
"These findings are particularly important for older Americans," said Dr. Richard J. Hodes, NIA Director. "Isolated systolic hypertension is the most common form of high blood pressure among people age 60 and older. It is a major risk factor for heart disease and stroke, the number one and number three killers of Americans today."
In isolated systolic hypertension (ISH), the systolic blood pressure is high (140 or greater millimeters of mercury, or mmHg) but the diastolic is normal (less than 90 mmHg). Millions of Americans over age 60 have ISH and more than 3 million have the degree of ISH treated in SHEP--a systolic of 160-219 mmHg and a normal diastolic.
High blood pressure is the chief risk factor for heart failure, which occurs when the heart loses its ability to pump enough blood through the body. Heart failure affects about 4.8 million Americans--3.4 million age 60 or older. It causes about 875,000 hospitalizations a year and is the most common diagnosis for hospital admissions in those age 65 or older. Half of those with heart failure die within 5 years of diagnosis.
Earlier SHEP results showed that treatment with a low-dose diuretic greatly reduces fatal and non-fatal strokes and cardiovascular events among older persons, including those with diabetes. The new findings focus on whether antihypertensive therapy prevents heart failure.
SHEP followed 4,736 men and women, aged 60 and older, for an average of 4.5 years. At the start of the trial, 492 of the patients had already had a heart attack.
Patients were randomly assigned to receive either a placebo or a low-dose diuretic (chlorthalidone) and, if needed, a second drug. The second drug was a low-dose of either a beta blocker (atenolol) or an adrenergic antagonist (reserpine).
Fatal and nonfatal cases of heart failure dropped dramatically with treatment. Even those age 80 and older benefited from treatment. The greatest benefits were for those who had had a heart attack before participating in the trial.
The following SHEP investigators are available to comment on the trial: Dr. John B. Kostis, lead author and Chairman, Department of Medicine, University of Medicine and Dentistry of New Jersey (UMDNJ)--Robert Wood Johnson Medical School, New Brunswick, NJ; Dr. Jeffrey Cutler, Director, NHLBI Clinical Applications and Prevention Program. Also available to comment is Dr. Andre J. Premen, Geriatrics Program, NIA.
To contact Dr. Kostis, call Tom Capezzuto of the UMDNJ News Service Department at (973) 972-7273. Dr. Cutler can be reached through the NHLBI Communications Office at (301) 496-4236 and Dr. Premen through the NIA Public Information Office at (301) 496-1752.