Studies raise questions on how best to treat high blood pressure
Recent studies on managing high blood pressure are throwing into question the current guidelines held by the American Heart Association (AHA), the American College of Cardiology and the Centers for Disease Control and Prevention (CDC) and practiced by millions of health care providers.
One-third of American adults have high blood pressure, according to the AHA, with readings of 140/90 millimeters of mercury or higher. For patients with hypertension, or high blood pressure, the association recommends treatment starting with lifestyle changes and then medication to reduce readings to levels below 140/90 until age 80 and 150/90 for people older than age 80.
Dr. Tom Barringer, the co-medical director of Novant Health Heart & Vascular Institute, said there are three different guidelines now and a new recommendation is expected next year. He said that based on all of the most recent trials, the consensus ideal blood pressure reading is below 130/80 for people with an elevated risk of coronary heart disease, stroke and kidney issues.
“Usually, the first line of treatment for patients involves diet, weight loss and exercise,” he said. “Lowering salt intake with a diet such as the DASH diet (Dietary Approach to Stop Hypertension) is effective at lowering blood pressure. Losing weight can also help people lower their blood pressure.”
However, lifestyle changes might not work for everyone to reduce blood pressure, he said. “When patients have had three elevated blood pressure readings, it’s time to consider medication.”
High blood pressure contributed to more than 360,000 U.S. deaths in 2013, according to the CDC. The World Health Organization estimates that hypertension accounts for 7.5 million deaths globally.
But recently released studies are challenging existing recommendations. In late 2015, researchers published a study in the New England Journal of Medicine that found more aggressive treatment of high blood pressure could significantly lower the risk of cardiovascular disease and death.
The findings of the Systolic Blood Pressure Intervention Trial (SPRINT) support a steeper goal of reducing systolic blood pressure (top number) to 120. Such a reduction could mean that millions more Americans would take medication to manage high blood pressure.
The study found that hitting the lower 120 target reduced the risk of dying from cardiovascular causes by 43 percent. However, concern remains with pushing blood pressure below 140 among older patients who may be more sensitive to medication and subject to side effects such as dizziness, which can lead to falls.
Barringer said there was a caveat on the study. “The SPRINT trial showed there was a benefit from a systolic blood pressure of 121 as opposed to 135, but it came with a price,” he said. “Though there were fewer cardiac events, there was an increase in fainting, lower potassium levels and higher kidney injury.”
“The ideal 120 over 80 reading is really not achievable in older patients,” he added.
Another study, Heart Outcomes Prevention Evaluation 3 or HOPE-3, raised some interesting questions as well. Participants in the study had at least one cardiovascular risk factor such as high cholesterol but had not been diagnosed with cardiovascular disease. During the trial, participants either received common medications to treat hypertension or a placebo.
The researchers found that blood pressure medicine was effective in lowering blood pressure. However, after nearly six years of follow-up, participants with lower blood pressure didn’t really equate to a reduced risk of death from cardiovascular causes. Death from heart attack and stroke occurred in 3.5 percent of patients who received the drugs and 5 percent of patients on placebo.
The finding from the HOPE-3 has experts wondering why pushing blood pressure to lower levels is not producing the benefit expected, even in individuals with a modest risk of heart attack.
Barringer said that the patients in the HOPE-3 study were at lower risk than those in the SPRINT trial. Those in the HOPE-3 who were in the group to receive treatment instead of the placebo were all given the same medication and after treatment it was found that blood pressure risk didn’t really change at all. “The difference between those treated and not treated was very small,” Barringer said. “Also, the treatment was started at a lower blood pressure threshold than in the range we normally treat patients and in younger patients.”
Barringer said the best advice he has for patients with high blood pressure is to monitor their pressure at home at least once a week with an upper arm cuff. “Readings fluctuate widely and after seven weeks or so, you will have a rather accurate sense of your blood pressure,” he said. “These readings will greatly supplement your provider’s insight into your cardiac health.”
Barringer also recommends downloading an app to track your blood pressure because it will help you assess your average blood pressure.
For those with high blood pressure, the AHA urges individuals to take charge of their heart health and follow these five steps:
- Know your numbers.
- Make a plan with your provider to lower your blood pressure.
- Make recommended lifestyle changes.
- Keep checking your blood pressure at home.
- Take medication as prescribed.
How’s your heart health?
Novant Health has launched a communitywide campaign called the 10,000 Healthy Hearts Challenge with a goal to educate 10,000 people about their heart health by 2018. Take the online heart health risk assessment, which analyzes cardiovascular risk factors, such as blood pressure, cigarette smoking, diabetes and body mass index. Then, tag five friends on social media using #NHHealthyHearts to spread the word.
Once you accept the challenge, look for helpful wellness tips, recipe ideas and stress management reminders sent to your inbox to manage your heart health.