Hypertension: How Low Should You Go?

Podcast Transcript

Dr. Scott Steele: Butts and Guts, a Cleveland Clinic podcast exploring your digestive and surgical health from end to end.

Dr. Scott Steele: Hi everyone, and welcome to another episode of Butts and Guts. I'm your host, Scott Steele, the Chair of Colorectal Surgery here at the Cleveland Clinic in beautiful Cleveland, Ohio. And today I'm very pleased to have Dr. George Thomas, who's a staff nephrologist and Director of the Center for Blood Pressure Disorders in the Department of Kidney Medicine. We're going to talk a little bit about "Hypertension: How Low Should You Go?" Dr. Thomas, thanks for joining us on Butts and Guts.

Dr. George Thomas: Thank you so much. Pleasure to be here.

Dr. Scott Steele: So, as we jump into this, go ahead and tell us a little bit about your background. Where'd you train, where you're from, and how did it come to the point that you're here at the Cleveland Clinic?

Dr. George Thomas: So, I've had a bit of a long journey, I should say. I completed medical school in India, came to the U.S. about 20 years ago, did a course in public health in Baltimore, did a couple of years of research after that, did my internal medicine residency training in Boston, then moved to Cleveland to the Cleveland Clinic to do my nephrology fellowship. And I stayed on as staff after fellowship. I've been here for about 12 years on staff. I think I developed an interest in hypertension during my fellowship years and during my early years as junior staff, and I now direct the Hypertension Center in the department.

Dr. Scott Steele: Well, we're super excited to have you here today. So today we're going to talk a little bit about hypertension. We got a lot of listeners out there. And to start, can you just give us a little bit of an overview about how blood pressure works in the body, and then how is somebody diagnosed with hypertension?

Dr. George Thomas: When the heart beats, it creates a pressure or a force that pushes blood through the network of tubes, the blood vessels. So, this force, or pressure, is blood pressure. Now, there's two aspects to this. One is the systolic blood pressure. That's the upper number that you see on your blood pressure reading, and that is the pressure when the heart is actually squeezing or pumping the blood out. The other number is the diastolic blood pressure, which is the lower number in your reading, and that's the pressure in the blood vessels when your heart is relaxed in between beets. So, this is why you see the systolic and diastolic blood pressure reading.

Now what happens is when that force or pressure is high over time, the lining of the blood vessels can get damaged, there can be inflammation, there can be cholesterol deposition atherosclerosis, narrowing, and the heart and the blood vessels have to work harder to push the blood out. This becomes a vicious cycle, and eventually there's organ damage. Now, one of the comparisons I can make is to water flowing through a garden hose. So, if the force is consistently high over time, that hose is going to get damaged. Or, if that hose is narrow for whatever reason, if there's narrowing, there's higher pressure across the narrowed part.

Now what people don't realize is that high blood pressure is causing damage in the initial stages. In the early phases, people don't realize that there's something going on. It's only when the damage is significant that sometimes people realize, "Oh, I've had uncontrolled blood pressure for a long time." So, it's important to track your blood pressure regularly to prevent this eventual organ damage from happening.

Now as far as hypertension is diagnosed, generally, most people when they go to the doctor's office, they have their blood pressure checked. That's one of the vital signs that is checked in the doctor's office. That's when you probably first have an idea of what your numbers are. And it's important to know what your numbers are because that determines what your risk is eventually.

Now, based on studies, guidelines now define hypertension as a number about 130 systolic or 80 diastolic. So about 130 over 80 is what's considered hypertension or a diagnosis of hypertension at this point. Completely normal blood pressure is less than 120 and less than 80. So, that's how we define hypertension. Again, most of the time people get an idea of their blood pressures in the doctor's office, but I always advocate for my patients to have blood pressures checked at home because you get a better sense of what's going on during your usual course of activities.

Dr. Scott Steele: So, we have a segment here that's called "Truth or Myth." So, is it true, or is it a myth?

So, Truth or Myth: someone is at more risk for hypertension if they have a family history of high blood pressure, cardiovascular disease, or diabetes.

Dr. George Thomas: I would say yes, that's the truth. So, when you look at hypertension, the majority of patients with hypertension have what we call primary hypertension. So, there's no one specific cause for that hypertension, but there are a number of risk factors. And one of these risk factors is family history. So, essentially, when you think of family history, you think about genetics and genes. There is no one hypertension gene per se, but there are multiple genetic risk variants. So, if you have parents with hypertension, there is more likelihood that you have those genetic risk variants that predispose you to having hypertension.

So, in fact, studies have shown that you are at a two to two-and-a-half times higher risk of developing hypertension if your parents have hypertension. Now, keep in mind that it's not just genetics. There's a complex interplay of genetics with and environmental factors that eventually lead to the phenotype of hypertension. So, it's not just a genetic predisposition; it's also your lifestyle factors, your diet, your weight, your sodium intake. All of those can play into developing hypertension, not just genetics. But having a strong family history is definitely a risk factor.

Dr. Scott Steele: So, we are a Butts and Guts episode here. So, how does your gut health impact your blood pressure?

Dr. George Thomas: That is an interesting question, and it is an interesting area of research. So, we know that gut health or the gut microbiome does have a role to play in health, including cardiovascular health. There are animal studies and human studies that have shown that disruption of the gut microbiome - that community of microorganisms in the gut - that disruption of that microbiome or less diversity in the microbiome can be associated with high blood pressures or even impact the efficacy of some blood pressure medications.

Now certainly, we need more understanding and more research into this. And hopefully in the future with more understanding, we can even potentially modulate the gut microbiome as a treatment strategy for hypertension. So, certainly, an interesting area of research that we need to understand more.

Dr. Scott Steele: So, can high blood pressure affect your kidneys and lead to other serious conditions?

Dr. George Thomas: Yes, high blood pressure affects your kidneys. It can cause kidney disease, it can cause stroke, it can cause heart attacks, it can cause heart failure. So, there's a whole lot of badness with high blood pressure. And the way it works is if you think about the high blood pressure flowing through the blood vessels, the damage to the blood vessels, the narrowing and inflammation and cholesterol deposition in the damaged areas cause narrowing of the blood vessels, which can lead to heart disease, if there's narrowing in the coronary arteries. It can lead to damage to the kidneys and to the brain with stroke. When those organs are affected, the heart has to pump harder to push blood when your vessels are narrowed. So, eventually, the heart muscles get thickened. You get what's called left ventricle hypertrophy and heart failure.

So, all of these, what we call "end organ damage" can be a consequence of uncontrolled high blood pressure, especially over time. So, it's important to get this under control at the earliest rather than waiting until the end when there is significant damage. So, hypertension is called a silent killer because you do not have any symptoms in the early phases when you have high blood pressure. You don't know that you have high blood pressure until the damage is pretty significant. So, it's important to track your numbers regularly.

Dr. Scott Steele: So, can you talk a little bit about the treatment options that are available for people with hypertension, as well as maybe the lifestyle or diet changes to maintain a healthy blood pressure?

Dr. George Thomas: So, the way we approach management of hypertension is two pronged. So, there's two big buckets, I would say. One is lifestyle modification, and that's perhaps something that is not stressed enough because patients and doctors sometimes may think that medications need to be added, changed without enough emphasis on the lifestyle modifications. So, lifestyle modifications are important even if you are on treatment to get your blood pressures better controlled. The lifestyle modifications that have really been studied extensively are a low-salt diet, a low-sodium diet, the DASH diet, which is high in vegetables, fruits, high in grain, low fat, that has been proven to be effective for blood pressure control, weight management, physical activity - at least 150 minutes per week is the recommended guideline - and limiting alcohol use. So, these are the tried and tested lifestyle modifications that are recommended in every guideline, and I think we should continue to reinforce this to everyone, to our patients, and everybody should be aware of these lifestyle modifications.

The second thing is, of course, the medications. You need medications many times to control your blood pressure. And the four big classes of medications that are available, we can remember it as A, B, C, and D. A is a class of medications called ACE inhibitors or ARBs, angiotensin converting enzyme inhibitors or angiotensin receptor blockers, B is beta blockers, C is calcium channel blockers, and D is diuretics. So, at this point, guidelines recommend A, C or D as first line treatment. B, or beta blockers, are generally recommended if you have some underlying heart condition, but not necessarily as first line. But any of the A, C or D medications can be used as first line medications.

Now certainly, there can be a trial-and-error period where some medications may work better for some patients compared to others. You may have side effects from medications. And that's an ongoing conversation with your doctor to come up with the ideal regimen that keeps your blood pressure under check and with minimal side effects.

Dr. Scott Steele: So, is there a thing - let's go to the opposite end of the spectrum now - is there something that is too low when lowering your blood pressure?

Dr. George Thomas: The simple answer is yes. There can be both extremes of high blood pressure and low blood pressure. Now, when we come to treating hypertension with studies and guidelines, the current goal for somebody who is on treatment for hypertension is to get their blood pressure to less than 130 systolic. Now, within the frame of the guidelines, we need to understand that not many patients may tolerate lowering their blood pressure too much. So, that's where science meets the art of medicine. We have to have an individualized approach to each patient because everybody has unique characteristics, tolerances, preferences. So, we have to come up with a goal range of blood pressures that would be best for that particular patient, avoid extremes of high or low.

Now certainly if somebody is used to running in the blood pressures of 120 to 130 systolic, let's say, and if they drop down to 90 systolic, they are going to be symptomatic. They're going to have lightheadedness, dizziness, and the other big question would be why did they drop their blood pressures that low? Could it be some medical condition that's going on that's causing their blood pressures to drop too much? Could they be bleeding? Could they be having a severe infection or sepsis? Do their medications need to be adjusted so that they don't drop that low and have symptoms? So really, within the framework of the guidelines, we need to individualize our treatment approaches because not one size fits all. So, certainly, I would say yes, there is a thing as blood pressure going too low, and as doctors, what we try to do is avoid the extremes.

Dr. Scott Steele: So, what is the outlook for somebody living with high blood pressure?

Dr. George Thomas: So, the outlook, again - the prognosis, the outlook - it depends on how good your blood pressure control is. So, if you look at studies, for example, the SPRINT study was a landmark study in hypertension, which compared a goal blood pressure of less than 120 to less than 140. And certainly, those who were able to control their blood pressure to less than 120 had a much more significant reduction in their cardiovascular risk or death by at least 25 percent. So lower blood pressure seems to be better than having relatively higher blood pressure.

Now, even in patients at a younger age, say 18 to 30, there are studies which show that compared to completely normal blood pressure, higher blood pressures have up to a 70 to 75 percent increased risk of cardiovascular disease and stroke. So certainly, controlling blood pressure pretends to be a better outcome than having higher blood pressures that are uncontrolled. So, the prognosis, I would say overall, is good depending on the degree of control that you have or depending on the degree of length of time that you have it controlled for.

Dr. Scott Steele: So, George, are there any advancements on the horizon for diagnosing or treating hypertension?

Dr. George Thomas: Yes, actually, these are some exciting times for hypertension. We do have newer medications in the pipeline, particularly targeting the renin angiotensin system. That's one of the factors that plays a role in blood pressure regulations. So, these are medications that are currently being studied, and some positive research outcomes with these medications. Maybe within the next few years, we'll have these medications as part of our treatment option. The other exciting part of therapies available is what we call device-based therapies - or currently experimental. But these device therapies can take the place of medications or can be an adjunct to medications. So, one of the device therapies that has caught a lot of attention is something called renal denervation. So essentially, it's a catheter-based procedure where we go in and ablate the renal nerves. The idea is that these renal nerves transmit sympathetic signals and the sympathetic system, if it's overactive, causes high blood pressure. So, ablating these renal nerves hopefully decreases sympathetic signaling and thereby decreases blood pressure. So, there are some positive studies out there that show a significant reduction in blood pressure with this denervation procedure. It's not FDA approved yet in the U.S., so hopefully that comes soon and then we can have this as a potential treatment option for our patients, especially in those who may be unable to tolerate adding medications or those who have polypharmacy and side effects to medications. This may be a good treatment option for these patients. So certainly, in the next few years, we may have both medication and device options for treating hypertension.

Dr. Scott Steele: So now it's time for our quick hitters to get to know you a little bit better. So, first of all, what's your favorite food?

Dr. George Thomas: So, I'm Indian. I have to say it's Indian food that I love. It's a home-cooked meal. It's something called rice and lentils. It's called dahl. That's my comfort food.

Dr. Scott Steele: More of a cream-based or spicy or what are we talking about here?

Dr. George Thomas: Spicy, definitely spicy.

Dr. Scott Steele: There we go. So, what's your favorite sport to play or to watch?

Dr. George Thomas: Soccer for sure. This is the time to be a soccer fan, so I'm rooting for Argentina. Let's see what happens.

Dr. Scott Steele: So, what is your favorite place to travel?

Dr. George Thomas: So, my favorite place so far that I've been to is Hawaii. We would love to go there again. The second best I would say is coming close is Costa Rica. I have to say I'm from India and I haven't traveled extensively in India, so we are planning a trip where we hopefully can cover more of India. I'm from the South and studied in the Western part of India, so I would definitely love to explore the Northern and Eastern part that we haven't been able to. But so far, I would say yeah, Hawaii and Costa Rica have been my favorite places.

Dr. Scott Steele: Fantastic. And so, what's one of the things that you like about living here in Northeast Ohio?

Dr. George Thomas: I mentioned that I moved here from Boston. That was a little bit of a culture shock, initially. That was when we didn't have kids. But right now, and I've been here for 12 years, Cleveland, I think, has a way of sucking you in. To raise a family, I think this is a great place to be. It's a slow city, I would say, compared to something like Boston. More affordable. There's a good mix of places to go, events to attend. So, I love it here. The one downside more than me, I guess, my wife would bring up, is the weather, especially during the winters. That can be a little bit of a tough time for us, but otherwise, we love it here.

Dr. Scott Steele: Finally, as we go into this, what is a take-home message for our listeners regarding “Hypertension: How Low Should You Go?”

Dr. George Thomas: So, there's three things I would mention. One is, as I mentioned, you need to know your numbers. That can be at the doctor's office where you first know that you have high blood pressure. But the office reading, remember, is a snapshot. So, I always advocate for my patients to check blood pressure at home. So, make sure you follow the proper technique of checking blood pressures, make sure you've discussed with your doctor how to check it and have your blood pressure machine - if you're doing it at home - have your blood pressure machine checked at least once a year in the doctor's office just to make sure that you're getting comparable readings and it's not way off and inaccurate. So yeah, tracking blood pressure is important.

The second thing is lifestyle modifications. There's no way you can get away without monitoring your lifestyle and just using medications.

Third is medications. Again, most people need it. Medications only work if you take them the way you're supposed to. So, if you have a problem with taking your medications, whether it's side effects or intolerances, discuss that with your doctor. Just don't stop taking it. The other important thing is to keep track of what changes are made, whether it's doses or new medications, because so many doctors may be changing your blood pressure medications. It's important to know why and what change was made so that others are aware. It's always good to track your own medications or have family or friends help you with that. I always ask my patients to actually bring the pill bottles. So I know many patients use pill boxes for ease of taking medications, which is fine, but get your pill bottles to the office, to the doctor's office with you so we can confirm what the names of the medications are and what the doses are and whether it's accurate because many patients don't remember the names and these complicated complex doses and things like that, especially if there's multiple medications. So, it's always a good idea to bring your bottles with you. So, those are the big things I would say from a hypertension perspective.

Dr. Scott Steele: That's fantastic advice. And so, to learn more about scheduling an appointment, such as for hypertension, at the Cleveland Clinic, please call us at (866) 320-4573. That's (866) 320-4573. George, thanks so much for joining us on Butts and Guts.

Dr. George Thomas: Thank you so much, Scott. It was a pleasure.

Dr. Scott Steele: That wraps things up here at Cleveland Clinic. Until next time, thanks for listening to Butts and Guts.