- Aggressive treatment lowers risk of deaths across race, gender
- Increased risk of side effects requires careful management
Doctors may soon be working harder than ever to lower blood pressure in millions of patients because of new research showing it could save thousands of lives.
The study, planned to run five years, was stopped two years early in September after researchers determined the advantages of aggressive treatment of high blood pressure, often with four or more drugs, were so clear. The full findings from about 9,360 people, all at least 50 years old and without diabetes, were released Monday at a meeting of the American Heart Association in Orlando, Florida.
The benefits of aggressive blood-pressure treatment -- reductions of 43 percent in cardiovascular deaths and 25 percent in deaths from any cause -- were surprising, coming after another large trial failed to show the same benefit among people with diabetes. While the reasons for the difference should be found, the results should soon be incorporated into treatment guidelines and practice, said Jackson Wright, director of the Clinical Hypertension Program at University Hospital Case Medical Center in Cleveland.
“The benefits are consistent across race and gender, whether or not have you existing heart disease, and whether you’re above or below age 75,” said Wright, first author of the study published online today by the New England Journal of Medicine. “We now have data to base our recommendations on, data that we didn’t have before.”
One-Third of Adults
About 70 million Americans -- one in three U.S. adults -- have high blood pressure, generally defined as when systolic pressure, the “top” number measured by a blood pressure cuff, rises to 140 or above. At this level, blood is pressing outwards strongly on vessel walls, increasing the chances of heart attacks, strokes, kidney disease and other disorders.
The Systolic Blood Pressure Intervention Trial, or Sprint, tried to keep half of the enrolled patients, chosen at random, at or below the 140 mark while treating the other half more vigorously in an attempt to get their top number down to 120. About 28 percent of the patients in the study, conducted at sites across the U.S., were 75 years old or older, 30 percent were black, 35 percent were women, 20 percent had existing heart disease, and 30 percent had chronic kidney disease.
The approach to treatment was relatively successful, as the average systolic pressure in the aggressively treated group was about 121 at the time the study was stopped. However, aggressively treated patients were prescribed on average 2.8 blood pressure drugs, and a quarter were taking four or more. In the other group, patients took an average of 1.8 blood pressure drugs.
The study didn’t address questions about which drugs or combinations are most effective in lowering blood pressure or preventing deaths. Medications prescribed to some patients included generic diuretics, beta blockers and Edarbi, a blood-pressure drug sold by Takeda Pharmaceutical Co. and Arbor Pharmaceuticals LLC, both of which donated medicine to the study and weren’t involved otherwise.
While the results offer the hope for prevention , the study shows there are risks to the aggressive approach, said Harlan Krumholz, a Yale University cardiologist. About 4.7 percent of patients in the aggressively treated group had serious side effects, such as kidney injury or failure, fainting and severe low blood pressure. That compared with the 2.5 percent rate seen in the less aggressively treated group.
“It’s a terrific finding,” he said. “It’s an option for people to go lower, but no one should think that it’s a free ride. There is some risk.”
Adding the drugs that may be necessary to attain the lower blood pressure goal may itself pose difficulties, Krumholz said. Many people with high blood pressure may already be taking a host of other medications, and adding more raises the possibility of harmful interactions between them.
“With any new strategy, not everyone benefits,” he said. “It’s up to us as doctors to help people make informed choices about what levels they want to shoot for.”
Getting patients with high blood pressure down to the levels called for in the study may present a significant challenge, said Judith Hochman, a cardiologist and senior associate dean for clinical sciences at New York University School of Medicine.
“We have a tremendous amount of work to do as a cardiovascular community in actually getting patients to the targets we know are beneficial,” she said by telephone. “It was 140, and if it’s going to be 120, it will be even harder. But we’ve got to do it, at least when we can do so without causing major side effects.”
Both the American Heart Association and the American College of Cardiology have indicated plans to release new treatment guidelines next year, Wright said. While the study didn’t include people under age 50 or people with diabetes, experts may want to revise their recommendations in all groups, based on the study, said Aram Chobanian, a Boston University School of Medicine cardiologist.
“Unless some other results come out later as they do more analyses, it seems to be a game-changer,” said Chobanian, who wrote an accompanying editorial in the journal. “There have been a few remarkable studies that have come through over the years, a very few where one really takes note, and I think this is one of them.”