ORLANDO, Fla. (Reuters) - U.S. heart organizations drafting new treatment guidelines for hypertension will consider new research showing that aggressively lowering blood pressure can ward off death and other cardiac problems, but top cardiologists advised caution in how the information is applied to wide practice.
Once called the “silent killer,” high blood pressure can be brought under control with a wide array of medications, many sold as relatively inexpensive generics. About 70 million people in the United States live with hypertension.
The medical community has been divided over whether there is an optimal blood pressure level for such patients. A government-sponsored study of more than 9,300 hypertension patients ages 50 and older showed that death from heart-related causes fell 43 percent and heart failure rates dropped 38 percent when their systolic blood pressure was lowered below 120 versus those taken to a commonly used target of under 140.
The findings of the Sprint study, released on Monday at the American Heart Association annual meeting in Orlando, Florida, will figure into new hypertension guidelines being drafted by the AHA and the American College of Cardiology. Their work is expected to be completed next year.
“The writing panel will review and consider all available evidence, including the Sprint trial presented this week,” AHA and ACC said in a joint statement to Reuters.
The Sprint study findings could prove to be a turning point in the medical community’s approach to high blood pressure. The U.S. government’s National Institutes of Health stopped the planned five-year study in August, two years early, after independent monitors found such clear benefits that it felt a need to make them public.
Dr. Mariell Jessup of the University of Pennsylvania Medical Center, who chairs a panel helping to draft the guidelines, said she was happy to have the new evidence because it can be difficult to convince patients to take more medicines to prevent future problems.
“It’s really nice to be able to say, ‘This trial showed that this is where you need to be, because you’re going to live longer.’ That’s meaningful,” Jessup said.
Other cardiologists said the risks of more aggressive treatment need to be explored more rigorously before applying it widely. Patients in the 120 systolic blood pressure group, for example, had a higher rate of kidney injury or failure, as well as fainting, although there was no increase in injuries from falls.
Dr. Steven Nissen, the Cleveland Clinic’s chief of cardiology, said he would want to know which patients were likely to suffer kidney failure before changing his practice.
“The thing that makes me pay attention is the one improvement that is the most important one, and that is death,” Nissen said. “It’s a big effect. The mortality advantage is compelling.”
The two medical groups would not say whether they will recommend specific blood pressure targets for various patient populations. They spurred controversy among cardiologists two years ago with new cholesterol treatment guidelines that eliminated a target level for “bad” LDL cholesterol in favor of a more complicated method of assessing a patient’s individual risk for heart disease.
Reaching the 120 target in the Sprint study was accomplished in most patients by adding one additional medicine to their treatment, for an average of three versus the two used by those in the group whose blood pressure was lowered to 140.
The Sprint findings suggested one death would be prevented for every 90 patients treated to a target of 120.
“That’s enough to change guidelines,” but the potential side effects must be considered, said Dr. Raymond Gibbons, a former AHA president from the Mayo Clinic in Rochester, Minnesota.
The ACC considers a systolic blood pressure level of 140 and a diastolic level of 90 to be its standard, based on government-issued guidelines released in 2003.
A paper by a group of influential doctors published in the Journal of the American Medical Association in February 2014 found no compelling evidence for a specific target, but recommended a systolic level of 150 for patients over age 60. The lack of consensus on how to approach hypertension was a prime reason for undertaking the Sprint study.
“The information coming at me has been somewhat controversial, and smart people are disagreeing about where to set limits and when to initiate therapy,” said Dr. Patrick O’Gara, director of clinical cardiology at Brigham and Women’s Hospital in Boston and former ACC president.
O’Gara said he wants “all the right eyes to look at the (new) data and fold it into the context of all the other information we have about hypertension.”
The data needs to come quickly to the attention of the guideline-writing committee, O’Gara added.
“We should enjoy that we’ve got new information but ... be certain that we don’t do what we typically do, which is to extrapolate findings to a larger patient population,” said Dr. Clyde Yancy, chief of cardiology at Northwestern University’s Feinberg School of Medicine and a past AHA president.
Dr. Marc Pfeffer of Brigham and Women’s Hospital saw less reason for caution. Asked if the treatment guidelines should be changed as a result of Sprint, Pfeffer responded: “Yes. This is a big deal.”
Reporting by Bill Berkrot; Editing by Michele Gershberg and Will Dunham