Transcription:
High Blood Pressure in Children

Scott Webb: Welcome to Children's Health Checkup. I'm Scott Webb. And today, we are discussing high blood pressure in our kids. And I'm joined today by Dr. Smitha Vidi. She's a pediatric nephrologist at Children's Health and assistant professor at UT Southwestern. And I'm also joined by Dr. Alan Sing. He's a pediatric cardiologist at Pediatric Heart Specialists, a Children's Health Care Network partner.

Doctors, thanks so much for your time today. today we're going to educate parents about high blood pressure in children, so they can be aware of its risks and know how to help their children stay healthy. And Dr. Sing, I'm going to start with you. How many children are affected by high blood pressure? Has this number grown over the years? And if so, why?

Dr. Alan Sing: The usual way that we define hypertension is a high blood pressure that's measured on three separate occasions. And so using that definition, the usual numbers that sort of get thrown around on a regular basis are anywhere from 2% up to 3.5 to 4% or so. We're talking about prevalence. And the numbers are even higher when we talk about obese populations.

There are some studies that suggest that they have a three times higher rate of high blood pressure compared to patients who have normal weights. And then if you add that up to type 2 diabetes, so obesity with type two diabetes, that can get up to 13%. So there's certainly a variation depending on what kind of a subgroup you're in if you have other medical conditions.

And it's interesting, I feel to kind of compare this to what the adult percentages are. There was a recent survey that came out in 2020, last year, when they looked at adults and up to 45% of adults have hypertension, 20% or so in the 20 to 30 year olds, 54% in the 40s to the 50s and 74 to 75% in adults 60 and above. So certainly the pediatric population is not as high as adults, but we know that, these kids, if they get it at a young age, they're exposed to it much longer term than these adults. And so that's why we care about this as pediatricians.

And then in terms of, has the number grown over the years? It's interesting, there was a study that showed that there may have actually been a decrease. In the early 2000s, the prevalence was around 7 to 8%. And then by the 2016-2017 time period when this study was performed, that prevalence had dropped back down to what I had mentioned before 3.5 to 4%, but that's been pretty stable recently.

Scott Webb: Yeah. And as you say, if children develop this at a young age, of course, they're going to live with it for a much longer period of time, so that's why a diagnosis, you know, and early treatment would be indicated. So that's a natural question then for you, Dr. Vidi. Can you explain how blood pressure is measured and share what's considered a normal or healthy range for children?

Dr. Smitha Vidi: Measuring blood pressure correctly is very important to diagnose high blood pressure or hypertension. Everybody's blood pressure actually goes up when you're stressed or anxious, especially when kids are actually at the doctor's office, they are nervous and that's completely normal. So if your child has high blood pressure for the first time, your doctor would bring the child back and check blood pressures more frequently.

Dr. Sing was saying it's usually blood pressures gets check on more than two occasions at the doctor's office. This is to make sure that the blood pressure is really high and if the blood pressure is really high, that's when you would diagnose your child to have hypertension. But that's one of things which I would like to mention with regards to measurement of blood pressure, checking blood pressure using a stethoscope as well as the hand-inflated arm cuff like how a doctor checks in the office is the most accurate way to measure blood pressure. We use this method to diagnose hypertension. But again, it's not something feasible for families to do at home and it requires a lot of training. We, however, recommend automatic blood pressure machines, just because that's easier to use to measure blood pressures at home.

And a few things, which I would like the parents to be aware of as well when measuring blood pressure at home is that they should make sure that your child is sitting comfortably with the back and feet supported in a chair. They should be calm and quiet for five minutes before taking the blood pressure. Use the right sized cuff, not the wrist cuff because using a wrist cuff gives you falsely elevated blood pressure in pediatrics. And measure blood pressure in the arm with the elbow is supported, so the arm is at the level of the heart.

And we also recommend disregarding the first blood pressure reading when you check with an automatic machine, just because the first blood pressure is always high. But we tell the families to log in the second or the third blood pressure reading and, if the second or third blood pressure reading is usually high, then it's always better to repeat it again in five to 10 minutes prior to writing that down in the blood pressure log.

And the second part of the question with regards to what is a normal blood pressure in children, per the latest guidelines from the American Academy of Pediatrics, any blood pressure more than 120, the top number, and the bottom number more than 80 millimeters of mercury in teenagers is considered to be high like adults. But in younger children, which is 12 years and below, we have blood pressure percentile charts, which is based on age, gender and height that we use. And, if your child's blood pressure is greater than the 90th percentile, then your doctor will monitor the blood pressure more closely. And if your child's blood pressure is greater than the 95th percentile, then your doctor will refer your child to be seen by a specialist like a kidney doctor or a heart doctor to see if your child needs further tests.

Scott Webb: Yeah. And a lot of great suggestions there for how we can check blood pressure at home. And Dr. Sing, are there any signs of high blood pressure? How do we know and how do you detect it?

Dr. Alan Sing: Blood pressure has been termed the silent killer. And it's a little bit dramatic, but I think the reason that it's gotten that moniker is that many times there are no symptoms at all. Most of the time when we think about having some sort of health problem or an issue, there's a symptom of some kind like pain or a change in the way that somebody feels.

But many times, blood pressure doesn't have any symptoms. Now, certainly if you have very high blood pressure that rapidly is occurring, then patients will sometimes complain about headaches or blurry vision or even getting nosebleeds. Some patients, they feel very tired and a term that a couple of patients have recently mentioned to me is that they just feel crummy. They have a hard time giving a voice to a specific symptom that they feel, but they just don't feel good. But that's certainly the minority of patients. Most of the time, they don't have symptoms.

But in terms of what's happening in the body, there can be negative impacts, signs of damage to different organ systems in the body, like the eyes, the brain, the kidneys, and the heart. But again, many of these may not be felt in any way. The challenge of high blood pressure, of diagnosing that, is it sounds obvious, but you can't tell unless you actually measure it. And most people don't go around checking their blood pressure for fun, unless you’re at the pharmacy and you saw the blood pressure cuff there. But most of the time, we check it on our routine screening evaluations at a routine annual visits at your PCP's office or when you go to the doctors for some other reasons.

So that's why it is important to get that checked on a regular basis as a screening measure so that when people do have high blood pressure, it doesn't go undiagnosed and untreated for long periods of time.

Scott Webb: And Dr. Vidi, what can cause high blood pressure in children?

Dr. Smitha Vidi: Well, there's actually a number of causes. But I would say the major cause is -- Dr. Sing already mentioned a little bit about this earlier -- is a growing trend in the number of cases of patients who are overweight or obese, and so that itself can actually cause   blood pressure to go up, especially in children.

And high salt diet. Can also be one of the biggest contributors to increase your blood pressure. and,

But other causes for high blood pressure, say if your child is actually born with any kidney abnormality, with any heart issues, and if you have any other endocrine problems related to thyroid and adrenal gland, and then there are a few other rare causes of hypertension, a few genetic causes of hypertension as well, which is seen in kids.

Scott Webb: And Dr. Sing, I've heard about something called white coat hypertension. That sounds interesting. What does that mean? And can it affect children as well?

Dr. Alan Sing: Yeah. So the definition of white coat hypertension is you have a patient who goes to the doctor's office. They see a doctor wearing a white coat, hence the term white coat hypertension. They get nervous. Their adrenaline increases a bit. And when you check their blood pressure, it's high, but it's makes sense, right? It's the fight or flight response where somebody is in an agitated state and their blood pressure's high.

But then if they go home and or somewhere else where they're not nervous and they check their blood pressure, then it's normal. And so it's basically when you have a high blood pressure in the doctor's office, but it's normal when you check it at home. And this can absolutely affect children. Some studies have suggested that a third and even up to a half of pediatric hypertension evaluations is actually truly white coat hypertension.

So the reason this is important is that, as part of these kids, when they get blood pressure workups, they get blood work, they have to give urine samples, they get referred to subspecialists, who may do more blood work, imaging studies like kidney ultrasounds, echocardiograms. And that's a lot of time and money in the healthcare system.

And if they actually just have white coat hypertension, a lot of this workup is unnecessary. And so it's really important. And fortunately, I think a lot of pediatricians are aware of this as an entity. Definitely, over-diagnosis and over-treatment of white coat hypertension is a major healthcare issue, not just in the pediatric world, but in the adult population as well.

Let's say you do have white coat hypertension. What does that actually mean? If we have patients who have normal blood pressure, and then we have patients who have elevated blood pressure all of the time. We imagine that patients with white coat hypertension, their risk profile for developing atherosclerosis or any kind of end-organ injury, it's probably more similar to patients who have normal blood pressure most of the time.

However, there are some studies that have come out recently probably in the last five to 10 years or so that suggested white coat hypertension may not be exactly as benign as we previously thought it was. There've been some studies that suggest that some of these patients, their rates of left ventricular hypertrophy, which is basically thickening of the main pumping chamber in the heart called the left ventricle, might be higher than the normal population.

And just to think about that a little bit, the blood pressure is what your heart has to pump against to get blood out to the rest of the body. And if the blood pressure is higher, then the heart has to work harder to overcome that blood pressure. And over time, if it's for an extended period of time, that can lead to negative changes in the heart, including thickening of the heart, stiffening of the heart and, even in more severe cases, dysfunction of the heart where it just doesn't squeeze as well. And there may be some evidence coming out that it may not be as benign, but it certainly is not as big of a problem as if the patient's blood pressures are high all of the time.

There is a particularly challenging situation though. There are some people who they get nervous at the doctor's office, but then they check it at home and it's fine. But there is a certain subset of people that they get nervous regardless of where they are. And it's not the physical location, but it's the actual act of checking the blood pressure, like the machine and the squeezing, and that makes them nervous.

And that's a tough situation, right? How can you accurately know what the blood pressure is when you're not nervous when every time you check it, you're nervous. And we fortunately have a specialized medical device called an ambulatory blood pressure monitor or an ABPM, that is very effective at even ruling out that kind of situation. Basically, you can preset it to check the blood pressure at certain time intervals, so it could be either every 20 to 30 minutes or so. There's a lot of evidence that suggests that it takes people about two hours to get used to that device, so we actually discard the first two hours of data. And then after that, we feel like the blood pressure profile that you can see on this device, it's a much more accurate picture of somebody's blood pressure versus checking it in the office or at home when there's significant anxiety in play.

Scott Webb: Dr. Vidi. what are the long-term consequences of undiagnosed hypertension in kids?

Dr. Smitha Vidi: So the latest recommendations by the American Academy of Pediatrics. It emphasizes on checking blood pressure in children during the routine visits with their pediatrician. This is to identify kids that have high blood pressure early and to treat them to prevent the long-term effects. High blood pressure, which is actually not treated can affect various organs in your body.

Kids can actually develop heart disease. They can develop kidney disease. It can affect your eye. They can affect the brain, you can also develop stroke. And, also, it's shown that you can actually develop thickening of your blood vessels in kids, who have uncontrolled hypertension for a very long time.

So the main goal is actually to identify these kids at risk for hypertension, to treat them early and to prevent all these long-term effects.

Scott Webb: And so we talk about treatment, Dr. Sing, how is high blood pressure treated in kids? And have there been any advances in measuring or treating high blood pressure that parents should know about?

Dr. Alan Sing: Dr. Vidi previously had mentioned some of those other causes of high blood pressure and we sort of break them up into primary hypertension and secondary hypertension. So primary hypertension is the blood pressure cases that are related to a poor diet, lack of exercise, obesity. And then you have the secondary hypertension, as she mentioned, which are caused by other medical problems.

And so, in order to treat blood pressure for patients who have secondary hypertension, certainly trying to focus on the underlying medical condition would be the first course of action. But then if you're talking about the patients who are in that primary hypertension category, it’s really about diet, exercise, and weight loss. There's a specific diet   called the DASH diet, D-A-S-H, and that stands for dietary approaches to stop hypertension. And this is a diet that strongly emphasizes increased fruit and vegetable intake, low fat dairy foods, and moderate amounts of whole grains, fish, poultry, and nuts. And specifically, limiting foods that are high in saturated fat, like fatty meats, tropical oils, like coconut or palm oil, and also limiting sugary beverages and sweets.

But perhaps the most important part of this diet is the sodium recommendations. The American Heart Association recommends a 2300-milligram amount of sodium in the daily intake or less than that. And there's also a secondary DASH diet called the lower sodium DASH diet that only recommends 1500 milligrams or less.

And just to put that into perspective, the average American diet has 3400 milligrams of sodium. And I'm sure there are some of us who have higher than that. We certainly want to avoid really high sodium intake.

And then for exercise, we recommend 30 to 60 minutes a day, three to five days a week or more. There's very robust data set that suggests that exercise not only improves the hypertension profile with patients, but also just overall cardiovascular health. And then we know that weight loss is very helpful as well. And then, in terms of what are the advances in measuring or treating high blood pressure, I really think that the ambulatory blood pressure monitor, that ABPM that I mentioned previously, while it's not necessarily a new technology, the 2017 American Academy of Pediatric blood pressure guidelines that came out, they really strongly emphasize increased usage of that device.

But I think the most important thing to treat blood pressure is to have a shared goal. It's very easy for a doctor to go into a patient's room. You see them for the first time, they have high blood pressure and just say, "Okay, go do a diet, exercise, weight loss." And there may not be buy-in with the family. And I think part of our job as a doctor is to convince people that, "Hey, we have a shared goal that we want to improve your long-term health outcome." And if they get buy into that, then many times our job is just to encourage them and to help them understand the personal benefits of what they're doing.   If we can try to do this without medication, that's certainly the preferable option. if a patient is not successful with lifestyle changes and they're still having blood pressure, even after you're trying to improve the diet, the exercise and the weight loss, then at a certain point, we would talk about doing a prescription blood pressure medication. I've found that trying to get people on the same page is the most effective way to treat blood pressure.

Scott Webb: Dr. Vidi, last word to you. Do you have any other advice or messages about high blood pressure that you want to share with parents?

Dr. Smitha Vidi: I would just like to echo what Dr. Sing said. I think the majority of the high blood pressures that we see in children again is because of all the weight and kids being obese or not eating the right diet. But trying to modify the diet, including more fruits and vegetables and nuts as we talked about, and, also if parents can actually devote like 30 minutes of your time each day doing fun activities with their kids, like biking, dancing, swimming, or even like taking a walk to the park, which I think is actually tough but trying to do that at least for like 30 minutes every day and trying to stay healthy is actually the key to prevent hypertension in children.

Scott Webb: For joining me today, a lot of great information. And thanks for listening to Children's Health Checkup. For more information, go to childrens.com.