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The Changing Guidelines of High Blood Pressure
When is your blood pressure considered high? Learn about the most recent guidelines from the American Heart Association, American College of Cardiology and other organizations.
Featured Speaker:
His current clinical focus includes caring for patients with a wide spectrum of cardiac conditions, as well as advanced expertise in transthoracic and transesophageal echocardiography, nuclear cardiology and vascular imaging.
Learn more about Dr. Amar Narula
Amar Narula, MD, FACC
Dr. Amar Narula received his medical degree from George Washington University School of Medicine in Washington, D.C. He completed his residency and internship at Columbia University School of Medicine and completed his fellowship training in cardiovascular diseases at New York University School of Medicine, both in New York City. He is board certified in cardiovascular disease, echocardiography, and nuclear cardiology. He is a registered physician in vascular interpretation.His current clinical focus includes caring for patients with a wide spectrum of cardiac conditions, as well as advanced expertise in transthoracic and transesophageal echocardiography, nuclear cardiology and vascular imaging.
Learn more about Dr. Amar Narula
Transcription:
The Changing Guidelines of High Blood Pressure
Maggie McKay: Having high blood pressure is not that uncommon. In fact, the CDC found that nearly half of the adult population in the US has it. But if you don't know you have it, that could put your health at risk. So, joining us is Dr. Amar Narula, cardiologist at Capital Health Cardiology Specialists, to tell us about the changing guidelines of high blood pressure.
This is Health Headlines Podcast Series from Capital Health. I'm Maggie McKay. Dr. Narula, thank you so much for being here today and making the time. Just to start off, what are the current guidelines for high blood pressure? Because I know when I go to my doctor every year for my annual checkup, they take your blood pressure, they tell you the numbers, and I always think, "Well, I don't know what they're supposed to be."
Dr. Amar Narula: Thank you, Maggie. Happy to join you. So, I think we'll get into the numbers. But before we get into what the current guidelines say about the numbers, it might be helpful just to say what the numbers actually represent. So when we speak to patients and lay people, we often say the top number and the bottom number. So, the top blood pressure number is called your systolic blood pressure. That's your blood pressure when the heart muscle is squeezing. The bottom number is called your diastolic blood pressure. That's your blood pressure when the heart muscle is relaxing. So, those are the two numbers that we reference in measuring patient's blood pressure.
So, the new guidelines have changed the bar a little bit in terms of the terminology we're using. And they describe 120/80 as the normal blood pressure, which is the same as kind of the guidelines have always been. But after that, there's been a change in terminology and cutoff points for hypertension. So, the new guidelines reference 120 to 129 on the top over 80 on the bottom as elevated. And then, stage 1 hypertension is now 130 to 139 on the top or 80 to 89 on the bottom. And stage 2 hypertension is greater than 140 on the top or greater than 90 on the bottom. So, this is redefined, you know what stage 1 hypertension is, dropping the bar from 140 to 130 and redefined what stage 2 hypertension is, and have also eliminated the terms pre-hypertension and replaced it with elevated.
Maggie McKay: Well, who sets the guidelines for what's considered high blood pressure?
Dr. Amar Narula: That's a good question, Maggie. A lot of times there's many societies that are involved and sometimes the guidelines can also be conflicting. The guideline we're talking about mainly today is a guideline issued by a whole host of societies, but headlined by the American College of Cardiology and the American Heart Association released in 2017. There is some discrepancy between these guidelines and previous hypertension guidelines that have been issued by the Joint National Committee, referenced JNC 7 and, the most recent one, 8. But these are the most up to date and newest guidelines, and they incorporate some data that wasn't present when older guidelines from JNC were released, even JNC 8.
Maggie McKay: And how often do the guidelines change, and why do they change?
Dr. Amar Narula: Right. So, I think the main driving point behind the change of these guidelines is when there's new data that informs decision-making, eventually the guidelines come around to incorporating that data and kind of shifting treatment approaches and treatment thresholds. So, the main change that happened in the incorporation of this guideline was in 2015, there was a large clinical study published, which took over 9,000 people at high cardiovascular risk and targeted them for achieving a blood pressure under 120 or under 140, calling that the intensive or the standard blood pressure targets. And when they completed the follow up of this trial, they found out not only was there a significantly lower risk of heart attack, stroke, heart failure or cardiovascular death, there was also lower rates of death overall by about 25% in the intensive target.
So, I think this study called the SPRINT trial was the main study that informed the new 2017 guidelines by the American Heart Association and the American College of Cardiology, not necessarily targeting such an intensive target of less than 120, but extrapolating that outward to the information that the previous targets may have been a little bit too lenient. You know, there's a couple facts about hypertension that are important to keep in mind that kind of substantiate this randomized clinical trial, which is a gold standard in medicine. A few of those facts are that, in 2010, hypertension was the leading cause of death and disability adjusted life years worldwide. And actually from a systolic blood pressure, our top number of 115 all the way up to 180, there's a progressive increase in risk. In fact, a 20-point increase in your top number and a 10-point increase in your bottom number are each associated with a doubling of your cardiovascular risk and stroke risk.
Maggie McKay: Wow. And so when it comes to different age groups, Dr. Narula, what are the different guidelines, or are there?
Dr. Amar Narula: Right. So, the guidelines for blood pressure similarly to guidelines for cholesterol and other things that have come out from cardiology societies, they're focusing more on a risk-based approach, not necessarily an age-based approach, especially for hypertension more so than cholesterol.
So, for hypertension, these guidelines apply to all adults. And the ranges are the same for all adults. But the difference is in the treatment algorithm for people who have established cardiovascular disease or are at high cardiovascular risk, which is defined as over a 10% 10-year risk of heart disease or stroke versus people who are at lower risk. So for people who have established heart disease or at high 10-year risk of heart disease or stroke, people that are very representative of that study that I mentioned earlier, the guidelines recommend for stage 1 hypertension, you institute both non-pharmacologic interventions and drug therapy to try to achieve your target.
Whereas for a second group of patients who are at low risk by absence of heart disease or a low 10-year risk, even if they have stage 1 hypertension, management can begin with non-drug therapy. But a crucial point here is that you need to have reassessment in three to six months. And if you don't have improvement, pharmacologic therapy should be considered. And in fact, in 2021, this same group kind of instituted an update to their original guidelines and kind of stressed this point that for, even these low risk patients, treatment should be considered to lower lifetime risk of cardiovascular disease.
Maggie McKay: Wow. That's good to know. If you have high blood pressure, but you don't know it, how dangerous is that?
Dr. Amar Narula: Yeah, it's dangerous. And I should mention one thing that I think is important that the guidelines point out very nicely that, before you label somebody with hypertension, it is important to have more than one assessment at more than one time. Because as cardiologists and even, you know, as any physician knows, white coat hypertension is very common, people get very anxious in the doctor's office and you can't judge hypertension based on one office visit or two office visits a year. You need to have an idea what the patient's blood pressure is doing in their standard settings. So you know, home blood pressure measurements, whether it's out-of-office self-monitoring or even ambulatory blood pressure monitoring that we can prescribe are important tools to use before you diagnose somebody with hypertension. So, you know, it's very common for, you know, people not to be aware they have this problem. Hypertension has commonly been known as a silent killer. But it's also very common to have white coat hypertension. So, that's a another thing that we need to focus on, and the guidelines point out very nicely. Don't just use one office reading at one physical, tell a patient they have hypertension and start a drug. Get additional data, whether it's ambulatory blood pressure monitoring or some other way you can substantiate those measurements
Maggie McKay: I know exactly what you're talking about, because every time they put that tight thing around my arm to take the high blood pressure, my heart starts racing. It's so crazy. And so, what are symptoms like if you think you're having symptoms, what are they?
Dr. Amar Narula: Potential symptoms are headache. Some patients describe just kind of feeling a fog in their brain or dizziness. And that's kind of the main thing we see clinically. Otherwise at the levels of blood pressure we're talking about, 130, 140, 150, the vast majority of people are asymptomatic. Sometimes people feel a little bit more anxious. Certainly as the blood pressure gets to more dangerous levels, 170, 180, 190, symptoms are more common, like shortness of breath with activity, sometimes even chest pain. But the goal of these guidelines are obviously to capture people before they get to those levels. But it's very important to, you know, get a physical, get your blood pressure checked.
And I'd like to take a minute also just to mention, in addition to drug therapy, the non-pharmacologic interventions are important too. Some of them have been shown to reduce blood pressure and we see this clinically as well. Some of the main ones are weight loss for people who are overweight or obese, restriction of dietary salt intake, increased physical activity and exercise and reduction of alcohol intake. And each of these things can have a four to five-point impact to your blood pressure. One study found that a DASH diet, which is low in sodium, saturated fat, and high in fruits and vegetables could decrease your top number by as much as 11 points. So, these are, you know, big, big differences. And certainly, like anything, there's synergistic benefits between diet, lifestyle, and drug therapy.
Maggie McKay: Dr. Narula, is there anything else you'd like to share that we didn't cover?
Dr. Amar Narula: Yeah. I'd make one more point. I know many patients are often hesitant to start a medication, start a drug therapy, worry about becoming dependent on it. What I like to tell my patients about hypertension is they're lucky, there's multiple drug classes which are effective with low risk of side effects. And what I like to tell them is I wouldn't walk around with a blood pressure that's elevated. You know, I would work on lifestyle. I would start a medication if you need to. And if lifestyle improves, if people lose weight, if people stop drinking alcohol and excess, or they restrict sodium or they follow some of these other non-pharmacologic interventions, it's very feasible and we do it all the time where this is a dynamic assessment and medications can even be taken away. So, it's not one of those things you want to ignore. It's one of those things you want to treat part of a team with your doctor and the patient, and it's a constant reassessment. So, there's a lot of options and the field is shifting and earlier treatment is more important. But lifestyle and drugs kind of work hand in hand.
Maggie McKay: That all sounds very hopeful. So, high blood pressure is reversible. Is that accurate?
Dr. Amar Narula: I think it's accurate. A lot of these things are things we see where people lose a specific amount of weight and we need to cut back in their medications. With aging, there's a lot of changes in the body that does promote the development of hypertension, and sometimes that can't be avoided, even despite a healthy lifestyle. But for a lot of America, where we're seeing higher rates of obesity, alcohol in excess, and an unhealthy diet, there's a huge lifestyle component to hypertension and that can definitely be reversed with a modification of those risk factors.
Maggie McKay: Thank you so much for sharing your expertise with us because this is really important information to know, especially since we looked at those statistics of about half of Americans have high blood pressure. So, this has been very informative. Thank you so much.
Dr. Amar Narula: Yeah, my pleasure. Happy to join you.
Maggie McKay: Once again, that's Dr. Amar Narula. And if you do not have a cardiologist and you're looking to schedule an appointment with one, please visit capitalhealthcardiology.org to find a location near you. And if you found this podcast helpful, please share it on your social channels and check out the full podcast library for topics of interest to you. This is Health Headlines Podcast series from Capital Health. I'm Maggie McKay. Thanks for listening.
The Changing Guidelines of High Blood Pressure
Maggie McKay: Having high blood pressure is not that uncommon. In fact, the CDC found that nearly half of the adult population in the US has it. But if you don't know you have it, that could put your health at risk. So, joining us is Dr. Amar Narula, cardiologist at Capital Health Cardiology Specialists, to tell us about the changing guidelines of high blood pressure.
This is Health Headlines Podcast Series from Capital Health. I'm Maggie McKay. Dr. Narula, thank you so much for being here today and making the time. Just to start off, what are the current guidelines for high blood pressure? Because I know when I go to my doctor every year for my annual checkup, they take your blood pressure, they tell you the numbers, and I always think, "Well, I don't know what they're supposed to be."
Dr. Amar Narula: Thank you, Maggie. Happy to join you. So, I think we'll get into the numbers. But before we get into what the current guidelines say about the numbers, it might be helpful just to say what the numbers actually represent. So when we speak to patients and lay people, we often say the top number and the bottom number. So, the top blood pressure number is called your systolic blood pressure. That's your blood pressure when the heart muscle is squeezing. The bottom number is called your diastolic blood pressure. That's your blood pressure when the heart muscle is relaxing. So, those are the two numbers that we reference in measuring patient's blood pressure.
So, the new guidelines have changed the bar a little bit in terms of the terminology we're using. And they describe 120/80 as the normal blood pressure, which is the same as kind of the guidelines have always been. But after that, there's been a change in terminology and cutoff points for hypertension. So, the new guidelines reference 120 to 129 on the top over 80 on the bottom as elevated. And then, stage 1 hypertension is now 130 to 139 on the top or 80 to 89 on the bottom. And stage 2 hypertension is greater than 140 on the top or greater than 90 on the bottom. So, this is redefined, you know what stage 1 hypertension is, dropping the bar from 140 to 130 and redefined what stage 2 hypertension is, and have also eliminated the terms pre-hypertension and replaced it with elevated.
Maggie McKay: Well, who sets the guidelines for what's considered high blood pressure?
Dr. Amar Narula: That's a good question, Maggie. A lot of times there's many societies that are involved and sometimes the guidelines can also be conflicting. The guideline we're talking about mainly today is a guideline issued by a whole host of societies, but headlined by the American College of Cardiology and the American Heart Association released in 2017. There is some discrepancy between these guidelines and previous hypertension guidelines that have been issued by the Joint National Committee, referenced JNC 7 and, the most recent one, 8. But these are the most up to date and newest guidelines, and they incorporate some data that wasn't present when older guidelines from JNC were released, even JNC 8.
Maggie McKay: And how often do the guidelines change, and why do they change?
Dr. Amar Narula: Right. So, I think the main driving point behind the change of these guidelines is when there's new data that informs decision-making, eventually the guidelines come around to incorporating that data and kind of shifting treatment approaches and treatment thresholds. So, the main change that happened in the incorporation of this guideline was in 2015, there was a large clinical study published, which took over 9,000 people at high cardiovascular risk and targeted them for achieving a blood pressure under 120 or under 140, calling that the intensive or the standard blood pressure targets. And when they completed the follow up of this trial, they found out not only was there a significantly lower risk of heart attack, stroke, heart failure or cardiovascular death, there was also lower rates of death overall by about 25% in the intensive target.
So, I think this study called the SPRINT trial was the main study that informed the new 2017 guidelines by the American Heart Association and the American College of Cardiology, not necessarily targeting such an intensive target of less than 120, but extrapolating that outward to the information that the previous targets may have been a little bit too lenient. You know, there's a couple facts about hypertension that are important to keep in mind that kind of substantiate this randomized clinical trial, which is a gold standard in medicine. A few of those facts are that, in 2010, hypertension was the leading cause of death and disability adjusted life years worldwide. And actually from a systolic blood pressure, our top number of 115 all the way up to 180, there's a progressive increase in risk. In fact, a 20-point increase in your top number and a 10-point increase in your bottom number are each associated with a doubling of your cardiovascular risk and stroke risk.
Maggie McKay: Wow. And so when it comes to different age groups, Dr. Narula, what are the different guidelines, or are there?
Dr. Amar Narula: Right. So, the guidelines for blood pressure similarly to guidelines for cholesterol and other things that have come out from cardiology societies, they're focusing more on a risk-based approach, not necessarily an age-based approach, especially for hypertension more so than cholesterol.
So, for hypertension, these guidelines apply to all adults. And the ranges are the same for all adults. But the difference is in the treatment algorithm for people who have established cardiovascular disease or are at high cardiovascular risk, which is defined as over a 10% 10-year risk of heart disease or stroke versus people who are at lower risk. So for people who have established heart disease or at high 10-year risk of heart disease or stroke, people that are very representative of that study that I mentioned earlier, the guidelines recommend for stage 1 hypertension, you institute both non-pharmacologic interventions and drug therapy to try to achieve your target.
Whereas for a second group of patients who are at low risk by absence of heart disease or a low 10-year risk, even if they have stage 1 hypertension, management can begin with non-drug therapy. But a crucial point here is that you need to have reassessment in three to six months. And if you don't have improvement, pharmacologic therapy should be considered. And in fact, in 2021, this same group kind of instituted an update to their original guidelines and kind of stressed this point that for, even these low risk patients, treatment should be considered to lower lifetime risk of cardiovascular disease.
Maggie McKay: Wow. That's good to know. If you have high blood pressure, but you don't know it, how dangerous is that?
Dr. Amar Narula: Yeah, it's dangerous. And I should mention one thing that I think is important that the guidelines point out very nicely that, before you label somebody with hypertension, it is important to have more than one assessment at more than one time. Because as cardiologists and even, you know, as any physician knows, white coat hypertension is very common, people get very anxious in the doctor's office and you can't judge hypertension based on one office visit or two office visits a year. You need to have an idea what the patient's blood pressure is doing in their standard settings. So you know, home blood pressure measurements, whether it's out-of-office self-monitoring or even ambulatory blood pressure monitoring that we can prescribe are important tools to use before you diagnose somebody with hypertension. So, you know, it's very common for, you know, people not to be aware they have this problem. Hypertension has commonly been known as a silent killer. But it's also very common to have white coat hypertension. So, that's a another thing that we need to focus on, and the guidelines point out very nicely. Don't just use one office reading at one physical, tell a patient they have hypertension and start a drug. Get additional data, whether it's ambulatory blood pressure monitoring or some other way you can substantiate those measurements
Maggie McKay: I know exactly what you're talking about, because every time they put that tight thing around my arm to take the high blood pressure, my heart starts racing. It's so crazy. And so, what are symptoms like if you think you're having symptoms, what are they?
Dr. Amar Narula: Potential symptoms are headache. Some patients describe just kind of feeling a fog in their brain or dizziness. And that's kind of the main thing we see clinically. Otherwise at the levels of blood pressure we're talking about, 130, 140, 150, the vast majority of people are asymptomatic. Sometimes people feel a little bit more anxious. Certainly as the blood pressure gets to more dangerous levels, 170, 180, 190, symptoms are more common, like shortness of breath with activity, sometimes even chest pain. But the goal of these guidelines are obviously to capture people before they get to those levels. But it's very important to, you know, get a physical, get your blood pressure checked.
And I'd like to take a minute also just to mention, in addition to drug therapy, the non-pharmacologic interventions are important too. Some of them have been shown to reduce blood pressure and we see this clinically as well. Some of the main ones are weight loss for people who are overweight or obese, restriction of dietary salt intake, increased physical activity and exercise and reduction of alcohol intake. And each of these things can have a four to five-point impact to your blood pressure. One study found that a DASH diet, which is low in sodium, saturated fat, and high in fruits and vegetables could decrease your top number by as much as 11 points. So, these are, you know, big, big differences. And certainly, like anything, there's synergistic benefits between diet, lifestyle, and drug therapy.
Maggie McKay: Dr. Narula, is there anything else you'd like to share that we didn't cover?
Dr. Amar Narula: Yeah. I'd make one more point. I know many patients are often hesitant to start a medication, start a drug therapy, worry about becoming dependent on it. What I like to tell my patients about hypertension is they're lucky, there's multiple drug classes which are effective with low risk of side effects. And what I like to tell them is I wouldn't walk around with a blood pressure that's elevated. You know, I would work on lifestyle. I would start a medication if you need to. And if lifestyle improves, if people lose weight, if people stop drinking alcohol and excess, or they restrict sodium or they follow some of these other non-pharmacologic interventions, it's very feasible and we do it all the time where this is a dynamic assessment and medications can even be taken away. So, it's not one of those things you want to ignore. It's one of those things you want to treat part of a team with your doctor and the patient, and it's a constant reassessment. So, there's a lot of options and the field is shifting and earlier treatment is more important. But lifestyle and drugs kind of work hand in hand.
Maggie McKay: That all sounds very hopeful. So, high blood pressure is reversible. Is that accurate?
Dr. Amar Narula: I think it's accurate. A lot of these things are things we see where people lose a specific amount of weight and we need to cut back in their medications. With aging, there's a lot of changes in the body that does promote the development of hypertension, and sometimes that can't be avoided, even despite a healthy lifestyle. But for a lot of America, where we're seeing higher rates of obesity, alcohol in excess, and an unhealthy diet, there's a huge lifestyle component to hypertension and that can definitely be reversed with a modification of those risk factors.
Maggie McKay: Thank you so much for sharing your expertise with us because this is really important information to know, especially since we looked at those statistics of about half of Americans have high blood pressure. So, this has been very informative. Thank you so much.
Dr. Amar Narula: Yeah, my pleasure. Happy to join you.
Maggie McKay: Once again, that's Dr. Amar Narula. And if you do not have a cardiologist and you're looking to schedule an appointment with one, please visit capitalhealthcardiology.org to find a location near you. And if you found this podcast helpful, please share it on your social channels and check out the full podcast library for topics of interest to you. This is Health Headlines Podcast series from Capital Health. I'm Maggie McKay. Thanks for listening.