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MED Cardiologist on What New Blood Pressure Recommendations Mean

“People don’t move guidelines; science moves guidelines”

  • American College of Cardiology issues new, stricter guidelines for hypertension
  • Low-risk people should change lifestyle if blood pressure is over 120/80
  • MED cardiologist Gary Balady discusses guidelines in Q&A

In November 2017, America’s leading heart experts released new guidelines for high blood pressure. Now, anyone with heart disease or with a 10 percent (or higher) risk of heart attack or stroke in the next decade (do a rough calculation here) should aim for blood pressure below 130/80, instead of the previous target of 140/90. Even for people without heart disease or significant risk, “lifestyle therapy”—less salt, no smoking, more veggies and exercise—now starts when blood pressure edges above 120/80.

This shifting bar means that the number of American adults with high blood pressure has suddenly risen from 72 million to 103 million.

BU Today talked with Gary Balady, a School of Medicine professor of medicine and director of preventive cardiology at Boston Medical Center, who has been a cardiologist for more than 30 years, to discuss the new guidelines. The interview has been edited and condensed for clarity.

Gary Balady, director of preventive cardiology at Boston Medical Center

Gary Balady, a MED professor and director of preventive cardiology at Boston Medical Center, says that lifestyle changes like diet and exercise should be the first prescription for lowering blood pressure. Photo by David Keough

BU Today: What does high blood pressure actually tell you about a person’s health?

Balady: Blood pressure reflects the pressure in your large blood vessels during the pumping phase and the relaxing phase of your heart. The pumping phase is the top number, called systolic, and the relaxing phase is the diastolic, the lower number.

One of the things that it does reflect, especially as we get older, is something called vascular stiffness—as we get older, our blood vessels become thicker and stiffer. And for the same amount of blood being ejected, there’s a higher pressure within the system. That higher pressure can cause troubles like stroke, in which small blood vessels in the brain break and lead to small hemorrhages. It can cause troubles like heart attack by increasing the work that the heart has to do.

The other area that’s related to blood pressure is the kidney. When the kidneys are exposed to high blood pressure over time, they begin to fail. So high blood pressure leads to heart attack, stroke, and kidney disease—those three things.

There was a hint that the guidelines would be changed in 2015, when researchers stopped the SPRINT study. What was the study and why was it stopped?

The SPRINT study looked at what a person’s optimal blood pressure should be, based on outcomes like heart attack, stroke, and combined total mortality. And the study found that a blood pressure of less than 120/80 was considered optimal.

For any age?

Yes, for every age.

And they found such strong evidence that they stopped the study early?

Yes, that’s correct.

American Heart Association blood pressure infographic

Source: American Heart Association

If I show up in your office and I have a blood pressure of 135/80, but I’m pretty healthy, would you put me on blood pressure medication?

Not necessarily. What is recommended is that we don’t base any treatment on one blood pressure reading. So maybe we take two blood pressures that same day, and perhaps if you’re in that range that is considered high but not dangerously high, we might bring you back in a week or a few months and recheck your blood pressure. In the meantime, we’ll sit down with you and talk about lifestyle measures that might help reduce blood pressure.

Like what?

Some of them relate to nutrition. There is a diet called the DASH diet (Dietary Approaches to Stop Hypertension) that’s been out for probably close to 20 years. And that’s a diet that promotes at least five servings a day of fruits and vegetables, which is not easy to do, high-grain products, limiting sugars and sweets to basically one serving a day, a handful of nuts every day, and lowfat dairy products. In addition, there’s a DASH diet plus low sodium. And what’s recommended is to keep sodium intake to less than 1,500 mg per day.

And exercise is great. Exercise can drop blood pressure by between 5 and 8 mm of mercury, systolic, which is almost as good as any single drug will do.

But if you came into my office with those blood pressure numbers, they’d suggest a repeat evaluation in three to six months.

So I’m not going to keel over immediately.

No, not at that level. Definitely not. The other thing that we would do is look at your overall risk profile. There’s a calculator called the ASCVD (atherosclerotic cardiovascular disease) risk score. And that looks at your age, gender, cholesterol level, presence of diabetes, blood pressure, whether or not you’re being treated with blood pressure medications. And based on those factors, we calculate a 10-year risk for your having a cardiovascular event. If your 10-year risk is calculated to be 10 percent or greater, then we might consider instituting drug therapy. We always start out with lifestyle, however, and give that a chance.

Most of the common blood pressure medications are now available as generics, so cost is less of an issue?

Yes, all of them are generic.

Doesn’t being over 65 automatically give you a 10 percent risk or higher?

That’s right.

When guidelines shift like this and suddenly a huge block of people are in a group they weren’t in before, sometimes people get frustrated.

People don’t move guidelines; science moves guidelines. And this particular group of scientists was well vetted, so they have no conflicts of interest with industry. Their objective was to review the science—good science, not poorly done studies—digest it, and put together what they gleaned from that literature. So based on that, plus emerging evidence in the field, the guidelines move. And they are moving toward what appears to be tighter restrictions or lower thresholds for treatment.

Do you remember any other occasion when another set of guidelines was changed?

Sure. The cholesterol guidelines.

Was it a similar thing? Lowering a threshold?

Yes, absolutely. The last set of cholesterol guidelines was in 2003, and then it was updated in 2013. Those guidelines shifted the threshold for treatment down, lower.

Does it ever go the other way?

Not until the evidence directs us to go that way.

I always think my blood pressure is higher when I go to the doctor. Is that a thing?

It is. It’s called “white coat hypertension.” And the guidelines actually spend a lot of time addressing that. If it’s repeatedly high in the office, then an ambulatory blood pressure monitor might be useful, where we would hook you up with a monitor that measures your blood pressure every five minutes or so throughout the day, and through the nighttime, and then gives us a printout of what your blood pressures are throughout the 24 hours. And based on those numbers, we would decide whether or not you indeed had white coat hypertension.

Does your blood pressure vary a lot throughout the day?

Yes, it does. So blood pressure will go up and down, primarily based on activity. But also if you’re acutely anxious about something, it can go up. And within 30 minutes of drinking coffee, blood pressure can go up a little bit.

Do you think ultimately these guidelines are going to help people? Or is it just going to end up putting a lot more borderline people on drugs?

That’s the challenge with any of these guidelines—the cholesterol guidelines, the blood pressure guidelines, any of these things. But they are intended to help people. No one wants a heart attack or a stroke, and people all want to live longer and healthier lives, and that’s the whole idea behind this.

4 Comments

4 Comments on MED Cardiologist on What New Blood Pressure Recommendations Mean

  • Mohammad javed on 01.31.2018 at 12:23 pm

    My sistolic bp always on higher side ie 170 whereas diasotolic remain at75. Tried all types of bp medicine but in vain. Pl advise suitable treatment. my age is 67 years.weight 70 kg.

    • Randy on 02.08.2018 at 3:24 am

      Hello Mohammad,

      If you don’t get any helpful information soon, please consider trying a site that may have ‘more foot traffic’ such as WebMD. I have no affiliation but would like you not waiting too long for help, just in case there would be something going on. If we don’t act ?pre/?pro actively we may not get the help we need. Sometimes we have be more aggressive to get answers. Please don’t wait too long.

      Best Of Health!

  • Betty L Staley on 02.03.2018 at 7:42 am

    I have high bp. I take medicine for it. I am not over weight, I eat fruits and veggies, I exercise. No matter what I do, I still cannot lower it. I am in the range of 145 to 150 over 85 to 90 most of the time. It worries me. I am 84 & 1/2 years of age. I have been very active my entire life and want to remain that way. What else can I do to lower my bp? Thank you.

    • Randy on 02.08.2018 at 3:13 am

      Hi Betty,

      Until someone truly qualified replies I have a though or two since I am close to someone who is being treated for related issues. Some things to consider with HBP: do you eat/ drink a lot of store bought foods? Do you drink sport drinks? Add salt to your foods? Most foods and drinks have trace to high amounts of sodium which can keep your numbers up even if you are doing everything else right. (Ketchup, sauces, Bread/ stuffing) Also, what kinds of caffeine products are in your diet? Are you getting enough fluids? and do you have family stressors, especially unresolved; or read/ watch a lot of News or TV dramas . . . these things can play a part.

      I doubt this is something, but either as a cause or a side effect, some people need an oxygen supplement to reduce health issues. Do you have a 90% Oxygen concentration in your blood? Does your doctor (or you) use a Pulse/ Oxygen meter to check your stats? If you are below 90% there may be something going on. If your doctor isn’t much help Try WebMD since it may have more traffic. Since I know people that have ‘slipped through so many cracks’ with primary care doctors, I try to get them to a good clinic or really any second opinion for feedback. Whatever is affordable or low Co-Pay, and not abusing public resources.
      Time un-diagnosed, if it would ever come to that, can make any treatment more arduous.

      On a personal note, you are quite inspiring! Keep up the great work.
      Good Luck and take Care.

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