Study: Lower blood pressure target may save lives
By Kevin McKeough
Suddenly, people with high blood pressure and their health care providers have a bigger chance of protecting their health, but also a bigger challenge doing it.
A major study has found that lowering one type of blood pressure to well below the commonly recommended level also greatly lowered the number of cardiovascular events and deaths among people at least 50 years old with high blood pressure.
That’s very big news, considering that approximately one out of every three adults in the U.S. has high blood pressure (also known as hypertension) — which puts them at risk for heart disease, stroke, kidney failure and other health problems. Adults more than 54 years old and blacks have even greater incidence of high blood pressure.
The National Heart, Lung and Blood Institute, which sponsored the study, announced some preliminary results on Sept. 11. The findings of the Systolic Blood Pressure Intervention Trial, or SPRINT, were so definitive that it was stopped earlier than planned in order to share the results quickly.
“When the amount or type of blood pressure medication was adjusted to achieve a systolic blood pressure target of 120 mmHg compared to the higher target of 140 mmHg, cardiovascular events such as heart attack, stroke and heart failure were reduced by almost one-third, and the risk of death by almost one-fourth, observes Lynne T. Braun, PhD, CNP, a nurse practitioner in the Rush Heart Center for Women. “That’s important information, because more lives may be saved and more deaths may be prevented if we maintain lower blood pressure in our patients.”
“Another thing that was important to note in this study was that it examined a very diverse population. It seems to apply across the board,” adds Braun, who was not involved in the study.
Braun, who also is a professor in the Department of Adult Health and Gerontological Nursing in the Rush University College of Nursing, offered the following insights into the study and its implication for high blood pressure patients and their care.
When is blood pressure considered too high, and how low was the target before the study results were announced?
Braun: High blood pressure is defined as a systolic blood pressure of 140 mmHg or greater and/or a diastolic blood pressure of 90 mmHg or greater. (Systolic and diastolic blood pressure measure the pressure on heart vessels when the heart is pumping and at rest, respectively. The acronym mmHg represents a common unit of pressure.) For quite a long time, the medical community has debated how low blood pressure should be lowered. Our goal was a blood pressure of less than 140 over 90 for most people, although guidelines published in 2013 stated that the target for people age 60 and older was less than 150/90 mmHg.
What should the new blood pressure target be based on these study findings?
Although we have some information about the results, we don’t know exactly how much blood pressure reduction occurred in order to achieve fewer cardiovascular disease events and deaths. We’re all being very cautious about this, because we want to see the full data. It’s supposed to be published before the end of the year.
At least we know systolic blood pressure should be below 140 and perhaps even lower. How is that information affecting how you care for your patients?
I’ve talked about it with patients. For example, I might see a patient who has a borderline blood pressure just above 140. I’ve said that down the road, it may not be good enough to keep you safe from heart attacks and strokes, and I tell them about this study. I ask what can we do.
I have to explore. If they’re on medication, is medication adherence an issue, do they take it as they should? What is their lifestyle? Is weight management an issue? What about sodium intake? Do they exercise? We go through the whole gamut of things about how we can get blood pressure controlled.
Will you try to get all your patients’ systolic blood pressure under 120?
It depends on the individual situation. If we have someone who is between 120 and 140, and if they’re on blood pressure medications or not, I would try to maximize lifestyle change at this point until I see all the data from the study.
But if somebody is between 140 and 150, I might think about increasing their dosage of the medication they’re taking. If they’re not doing much regarding lifestyle, and they’re willing to give it a good try, I would try that first.
It’s complicated, because it depends on what the risk factors are, whether they’ve already had a heart attack or stroke, if they’re overweight or obese. I would treat the person who is higher risk more aggressively sooner than somebody who only has high blood pressure and is at lower risk. Every person has to be evaluated as their own person, as an individual.
There’s some concern that it may take too much medication to get some patients’ blood pressure below 120, right?
It’s something we always have to keep in mind. We have to think about the number of medications we give people, whether or not there are drug interactions, whether or not there are side effects. There are other issues when you’re talking about multiple medications, such as cost, and adherence.
Realistically, we can’t get everybody down to 120. For an older person, it can be dangerous to keep them on so many medications that perhaps would cause unsafe side effects for them. diuretics (water pills), for example, can cause dehydration and dizziness in older people.
Sometimes we have to be happy having had some lowering of blood pressure with two or even three medications. Every patient needs to be treated individually.
You mentioned medication adherence. How do you handle it with patients?
I tell my patients it’s important that you take your medication every day as prescribed, and it’s important that you let me know if you think you’re having a side effect from the medicine, because we definitely will be able to provide an alternative. We have so many different blood pressure medications from different classes.
I also ask my patients to take their blood pressure at home. It helps my patients see the effect of their blood pressure treatments and helps me make better decisions about blood pressure management in the office.
What can you do besides medication to help patients reach this new target?
We always emphasize lifestyle changes in managing high blood pressure, because they do matter. If you walk 30 minutes a day, at least five times a week, you can reduce your blood pressure. If people who are overweight lose even five percent of their weight, their blood pressure will come down.
Across the board, we advise people to reduce their sodium intake, because Americans consume three to four times more salt than we need for adequate functioning of our bodies. Most people can cut back by doing things like not eating out as much, or requesting that their food is prepared with less salt, or not eating canned foods so much.
It’s important to maximize these lifestyle strategies anytime, because they’re healthy to begin with. They’re especially good for people who don’t have the blood pressure goal achieved that they should, and adding another drug might cause them side effects.
Good blood pressure control is important to prevent heart attacks, heart failure, strokes and kidney disease. Research like SPRINT helps us to know how far blood pressure should be lowered to prevent complications.