New details released today from a landmark study could lead to changes in blood pressure guidelines.
The study showed that in patients at high risk for heart problems, aiming for a systolic blood pressure -- the top number in a blood pressure reading -- of less than 120 mm Hg (millimeters of mercury) led to lower rates of serious cardiovascular events and death compared to patients whose target systolic blood pressure was 140 mm Hg.
The results from the Systolic Blood Pressure Intervention Trial (SPRINT) were presented at the American Heart Association Scientific Sessions in Orlando, Florida.
For the study, the researchers randomly assigned 9,361 participants with a systolic blood pressure of 130 mm Hg or higher and an increased cardiovascular risk, and who didn't have diabetes, to one of two groups: a standard treatment group in which the systolic blood pressure target was less than 140 mm Hg, or an intensive treatment group in which the target was less than 120 mm Hg. They tracked outcomes including heart attacks, acute coronary syndromes, stroke, heart failure, or death.
The study results, published in the New England Journal of Medicine, add toearlier findings released in September. At that time, study investigators stopped their research at 3.26 years, short of the originally planned five-year mark, due to the strength of the findings.
The researchers are now reporting a 25 percent reduction in cardiovascular events, including heart attack and stroke, and people in the aggressive treatment group were 27 percent less likely to die of any cause. The study also found a 43 percent reduction in heart-related deaths.
The landmark study from the National Institutes of Health shows clear benefits to reducing systolic blood pressure below 120 for patients over age 50 who are at risk for heart disease. Currently, guidelines recommend patients keep the top blood pressure number under 140, but experts say those recommendations could be revised in light of the latest findings.
"With this lower blood pressure, there was about a 35 percent relative risk reduction of cardiovascular disease. And that's tremendous," said cardiologist Dr. Suzanne Steinbaum of Lenox Hill Hospital in New York, who was not involved in the study. "We really need to be more aggressive about getting the blood pressure down."
The study authors wrote, "Among patients at high risk for cardiovascular events but without diabetes, targeting a systolic blood pressure of less than 120 mm Hg, as compared with less than 140 mm Hg, resulted in lower rates of fatal and nonfatal major cardiovascular events and death from any cause."
"These results reinforce the compelling public health importance of enhancing the awareness, treatment and control of hypertension in this country and around the world," said Gary H. Gibbons, M.D., director of the National Heart, Lung, and Blood Institute (NHLBI), the primary sponsor of SPRINT.
Historically, there has been some controversy over practice guidelines for treating hypertension, said Dr. Stacey Rosen, vice president of women's health at North Shore-LIJ's Katz Institute for Women's Health, in New Hyde Park, New York.
Rosen said the new findings will influence the way she treats and educates patients.
"In those already being treated, I will be careful to be sure I'm appropriately managing levels lower than I have done in past. And then in patients coming in who have never been diagnosed, I will use this data as another explanation for the need to be aggressive about treating hypertension in my patients," said Rosen.
Lower blood pressure did lead to some complications including low blood pressure, fainting, and kidney damage in some study participants.
One out of every three U.S. adults has high blood pressure, according to the American Heart Association.
One patient, Mary Rzepski, was once "near death" with complications from high blood pressure, but reduced it under the 120 mark with the help of medication and lifestyle changes.
"I am now at 69 much healthier than I was in my forties," Rzepski told CBS News. "I go to the gym, take yoga classes, I walk an hour a day seven days a week."
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