Ep 17 - Hypertension in Acute Medicine - Tony Heagerty
2:23PM Sep 16, 2022
high blood pressure
coronary artery disease
Welcome to the Royal College of Physicians of Edinburgh clinical conversations podcast each episode within this podcast series, we delve into a different medical topic with an expert speaker to join us. If you want to find more about the Royal College then please do head over to the RCP website and have a look at the Education stream and see if membership would work for you. It offers a host of educational updates and activities such as the evening medical updates, the World College symposia, and many more. Please don't forget if you listen to our podcast to give us a rating on one of the podcast platforms or subscribe so that it can come directly into your podcast stream. So welcome to today's episode of our clinical conversations podcast and today's episode is all about hypertension. Today we are lucky to have fessor Haggerty talking to us on some pearls of wisdom within hypertension. Professor Haggerty graduated from Middlesex Hospital. And after initial house officer jobs in Hatfield and Lester he embarked upon a period of research within the Department of Medicine in the University of Leicester. It was here that he developed service and research interests in the cardiovascular system. He was awarded his research MD in 1987, and then elected as a fellow of the Royal College of Physicians in 1989. His current post lies as professor of medicine in the University of Manchester based at Manchester Royal Infirmary. He is a consultant general physician with an interest in hypertension and other cardiovascular risk factors until 2005. Prof. Haggerty was president of the European Society of Hypertension and between 2008 and 2010 was president of the International Society of Hypertension. And until 2013 was president of the British hypertension society. He is also the editor in chief of the Journal of hypertension. His most recent award of many is the world hypertension League, Norman Campbell excellent award in population hypertension Prevention and Control 2022. We are delighted to have him here on this podcast to discuss the topic of hypertension today. So thank you very much for taking the time to chat to us and our audience. And I just wondered if you could give us a brief introduction on how you got into your job role with an interest in hypertension and what the fundamentals of hypertension are and the problems that it can bring within our patients.
I'll do my best. And I'll try and be brief. I was actually training in cardiology as a junior doctor. And it became clear in those days that you needed to do some research in order to further your career. And so I went to see Professor John swales in Leicester, who had an interest in hypertension. And he said that he could find me a position and I began a research career in hypertension. And I never went back to cardiology, because research was so much fun. And I have continued a lifelong interest in High Blood Pressure Research, both from a clinical perspective and from a laboratory based programme. And I've also had a clinical practice. So the problem is that everybody's got a blood pressure. It's a normal distribution. But unlike say height, or shoe size, the higher levels of blood pressure associated with an increased risk of stroke, heart failure and coronary artery disease. But perhaps what's more important is that trials of mild to moderate hypertension management in other words, lowering the blood pressure is associated with an amelioration of that risk. So if you normalise a patient's blood pressure, you can reduce their risk of stroke almost immediately. And the overall reduction is nearly 50% coronary artery disease takes a little longer, and perhaps the impact of hypertension management per se is less. But the overall benefits to the community at large are enormous. If you build into that the fast realisation that probably lowering blood pressure is also associated with a reduction in dementia, you can see that it has some major effect on community health. And if you then look at the nature of the problem in the United Kingdom, about 1/3 of individuals has an unacceptably high blood pressure. Not all of those will require drug therapy. Some can actually be managed by changes in lifestyle, but a significant number will end up on a drug therapy programme. And in doing so, they're practising preventative medicine and they will protect their circulation. It's as simple as that.
That's fascinating. And I think a really good way to start with how broad the issue is and how much that we can actually as doctors pick this up for a patient who predominantly will have no symptoms and no awareness that their blood pressure is An issue unless it gets tested and the fact that both the patient and the physician can do so much about it.
I mean, you're absolutely right, you take a simple blood pressure measurement, you probably want to do more than once or involve the patient in the programme of screening because people do get nervous about having their blood pressure taken. And they may actually have by and large, normal blood pressure. But faced with us as physicians, they get nervous and the blood pressure is artefacts really high. And we want to avoid unnecessary prescriptions for patients who don't really require it. Modern guidelines suggest the best way around that is to empower the patient. So either you do lots of readings over a 24 hour period, do an ambulatory blood pressure study, or the patient buys their own monitor and measures it at home, and you get much more reliable reading. So you filter out the white coat effect, and you target your therapy or your lifestyle measures to the patients who are genuinely hypertensive. And I guess as a rule of thumb that the practice points are consistent blood pressure in the office above 140. Over 90 is hypertensive consistent blood pressure above 130, over 85 on an ABPM and ambulatory blood pressure study or on a home monitor is hypertensive.
And I think that comes on really nicely to one of the first questions we can look into let's take maybe two patients, you've got a patient that comes into the acute receiving unit with something totally unrelated. And the whole time in there. They are hypertensive. They don't have a headache or any renal impact or anything else on finding and they are not known to be hypertensive. What should we be doing going forward with this patient?
We get a lot of this we get a lot of questions about this particular sort of issue, we would ask the GP to follow up that patient, if the presentation is pressure independent. In other words, it's just an incidental finding. And if the GPS find that the blood pressure is consistently elevated after discharge, then they can affect a programme of management. Most of hypertension can be managed in primary care. It's only the difficult cases that need to come into the secondary or tertiary sector, one might sit up and take a bit of notice if the patient presenting in a&e were young, because you might be thinking about a secondary cause. But in the absence of symptoms, the first thing would be to confirm that the hypertension is sustained. And that can be done in general practice. And then
I guess the other type of patient that we sometimes see may have been referred in through their GP or they may have walked in or come through a&e and they have classic when I can think of my mind as a patient presents with a headache and they also have high blood pressure and their blood pressure is reading 170 180 systolic the patient's clinically well how should we go about that case?
Okay, so you can divide those sorts of patients into hypertensive urgency and hypertensive emergency, the emergencies are easy because they've got evidence of organ damage. So if they've had a stroke or TIA dissected the aorta, chest pain, coronary artery disease, acute coronary syndrome, these patients need to have their blood pressure controlled quickly. And they need obviously the target organ damage to be limited for those that we call urgencies, your patients scenario headache, unless the headache is off sinister pathologies, such as that you'd see with a subarachnoid for example, but if it's just a straightforward headache, and they've got hypertension, two things you have to bear in mind, one is the headache may be driving the blood pressure. The second is the blood pressure may be driving the headache, but either way, there's no great urgency about lowering that individual's blood pressure. Most of these patients, when they call me up, I would just say, give the patient some analgesia for the headache, send the patient home, and either the GP consorted out or I will pick them up in my outpatient service. But there is no need to do anything other than reassure the patient and discharge them, they can be seen and managed at our leisure, we don't have to give them anything acute. I mean, if people are worried if the systolic is consistently above 180, or 200, you can start a therapy programme, they won't come to any harm. And depending on the age and the ethnicity of the patient, the selection of your drug will be made for you. But there's no urgency about controlling the blood pressure. And in fact, you can do more harm than good. If you screw the blood pressure down from say, 200 to 140. In 10 minutes, you could cause a stroke. So you don't want to do that.
I think that is really useful advice. And as you said, staying calm and not needing to act straight away is something that we can probably take on board soften or I want to fix a number rather than looking at the whole picture. So for your malignant hypertension or patients that do have end organ damage. How should we go about looking after these patients?
Okay, I'm going to divide that into two. If you see a patient with very high blood pressure, you define it as malignant if they've got evidence of proteinuria and retinal changes of grade three or grade four, which is haemorrhages and exudates plus minus papular edoema. If you've got that sort of patients need their blood pressure to be lower. If they haven't got any evidence of gross target organ damage, like dissection or a stroke, you can start them on oral medication. If they've got evidence of malignant phase blood pressure, and they've got problems of ongoing target organ damage, you'll have to give them intravenous drugs and most intensive care units use intravenous labetalol as their drug of choice, whilst co administering oral therapy as well assuming the patient can swallow the tablets and absorb them. So the idea then is to get the patient's blood pressure down. Now, you don't want to normalise it straightaway, you want to bring it down by 20 or 30 millimetres in the first 24 hours, the danger of any further target organ damage will disappear as a result of taking the edge off the blood pressure and then we can gradually get it down to normal over the next two or three days. So it's quite simple. Going back to the first patient with malignant phase hypotension. Probably the best drug to start with is a calcium channel blockers such as Amlodipine start with five milligrammes that will work pretty quickly, and you can increase the dose within a couple of days to 10. And then you can give a second drug if you need it, if you've got the patients with target organ damage, intravenous labetalol and the current administration of amlodipine. Once you've got the edge taken off the blood pressure with the intravenous compounds, you can introduce your oral therapy and tail off the intravenous stuff. This is Tiger country, if you're a bit scared, then get a senior along or phone up blood pressure man, but it's fairly easy stuff fairly straightforward.
Great. And I guess along with the medication, as you said earlier on, there's a lot of lifestyle stuff that the patients can do themselves. And I guess that's something that we as physicians can be chatting to our patients as we see them in these ambulatory care settings, acute units and on the wards about what they can do for themselves, especially as a lot of patients don't like taking medication, particularly, I guess, medications that they don't necessarily feel the immediate benefit from,
you make a good point, actually. And it's one that is emphasised in other countries, such as, say China and India, you go to a doctor in those areas, and usually you have something wrong with you, you get a short course of therapy, and you get better and then you stop it. And so there is a notorious problem there because people get their blood pressure picked up, they're given some treatment. And they think that after a month or so they can stop it and the blood pressure has been controlled and they don't need to go on taking it. So the message has to be emphasised that the therapy will probably be for life, you come back to this country, you're absolutely correct. Many of the patients don't want to take therapy, don't like taking therapy don't understand the reason for the therapy. And the message that you have to give them is that it's preventative. It's not because they're sick, they can carry out what would they would regard as a normal life. If they want to lift weights or run marathons. It's a question of the fact that keeping their blood pressure lower than it is before treatment will reduce the chances of developing end organ damage in the future. So then, if you come back to your original point about lifestyle, many hypertensives are overweight. And nearly every single study of weight loss is associated with a reduction in blood pressure. Many have a sedentary lifestyle, so a little bit of increase in exercise, we're not suggesting that they run every day 510 miles but a brisk walk for 30 or 40 minutes taking the stairs rather than the lift up a few floors, things like this is associated with a fall in blood pressure. And then something which is quite unappreciated is there is a huge problem with alcohol consumption in this country. And consistent high level of alcohol is associated with a sustained rise in blood pressure. So looking at alcohol intake is well worth doing and advising individuals to keep an eye on that is beneficial. Alcohol itself is an independent risk factor for stroke. So we want to make sure that they understand that as well. And the final point is nutrition. Although it's controversial, if you've got high blood pressure, and you have a good go at reducing the salt content of your diet, it will probably show a fall in your blood pressure it has to be a good go. In other words, you've got to restrict your intake to about five grammes a day maximum which for most people will be having your salt intake and there's a lot of salt in things that people like or don't know it's in there for example, chocolate, some breakfast cereals, bread, although the manufacturers over the last few years have reduced the salt content, it's still got a lot of salt in it and of course processed foods, but if you stick to it, the blood pressure will come down. And the other thing which may be beneficial is to increase the potassium intake your diet which would come from fresh fruit and of course alongside that you probably will increase your polyunsaturates and reduce your saturated fat intake and you can get those messages across two things may happen one as you say the patient may avoid blood pressure treatment completely. The second thing is they may actually reduce the number of tablets they have to take however they have to sustain the effort. The problem is Always by the American Heart Association is many patients actually give it up at a later date 12 months and you go back to the patient, they may be back to square one. So the message has to be reinforced.
Absolutely. That's all really interesting. And I guess as we get an elderly population, I thought we could have a chat about these patients at a target of 130 systolic for an elderly patient who's having falls may then start causing other issues. How should we be managing hypertension in the elderly patients who may have been on blood pressure tablets for many, many years,
the first thing to say is controlling blood pressure in elderly patients is still demonstrably beneficial. But you could divide that into two those who are de novo diagnosed, say above 80. We call that elderly for the sake of today, if you've not had your blood pressure measure before and you've not been treated, you will get extended healthy life if you have a blood pressure treatment programme. But you're absolutely right, there are associated risks. If you get the blood pressure down too low, the patient may develop postural symptoms, or even fall over and injure themselves. So the pragmatic approach is to get the blood pressure down in an 80 year old or older to about 150 over 80 and probably stopped there unless the patient's extraordinarily healthy and could go lower. Now, if you've got a patient who's coming through to old age, but has been treated for some time, and they're tolerating their therapy, there's no need to alter it. They just carry on your point, which is well made is that there is controversy now about the targets for effective blood pressure control. And if you take the people under 80, probably the target is 140. Over 90, the Americans would have us look at 130 over 80. And that is controversial. Still, the decision to change a target to 130 over 80 or less was made on an American trial called the SPRINT study, which did not include patients with a previous history of stroke, or did not include diabetic hypertensive. So it's not extrapolated to the whole hypertensive population. And also yes, I should say, within that study, frail patients and nursing home patients were not included. So they minimise the chances of postural falls, hypotension and injury or even renal failure. Even so there were an increased number of those events, but they did not achieve statistical significance. So you're probably okay, going down to 140 over 90. The other point to make in elderly patients is is predominantly systolic hypertension. And people are concerned that if you lower systolic diastolic, which is normal or very low, we'll go even lower. Don't worry about that focus on the systolic pressure.
That's really interesting. And finally, I guess another population group that we might not come across so often is women of childbearing age and pregnancy. Now, obviously, that splits up into pre existing hypertension, and then going into kind of the preeclampsia episodes, I guess, if a patient becomes pregnant, and they have pre existing hypertension, we obviously need to do some changes in their medications. And really, there should be elements of pre pregnancy planning, which doesn't always happen, I guess, what should we be doing with hypertensive pregnant patient?
First thing is timely, we're having this discussion because last week, New England Journal of Medicine may 12, carries a trial from the United States looking at treating mild hypertension in pregnancy, and demonstrating unequivocally that controlling blood pressure is associated with better outcomes. So we've got good evidence now if people want to look it up. Second thing to say is that a lot of women come to see me and they say I've had a miscarriage or I'm thinking of having a family in the future, and they've got hypertension, probably what I tell them is that we won't be using ACE inhibitors or angiotensin receptor blockers because they could damage any conceived foetus. You're absolutely right. There are patients who can see fast on those agents and you want to get them off those as quickly as possible. And the drugs that are considered safe in pregnancy would be calcium channel blockers, such as nifedipine, or amlodipine, labetalol, and alpha methyldopa. Those are the sort of three drugs that are probably most used, what I often do and what women would like to do, many women will come to me and they will say, I don't want to take any drugs while I'm trying to have a baby. And I say, right, fine. Stop your therapy unless there's a real problem like malignant hypertension or target organ damage, stop therapy conceive, we can start you on therapy after conception on a drug that safe in pregnancy, or monitor the pregnancy and introduce the therapy if necessary at a later stage in the trimesters and see how you get on and follow quite closely. And many women like that approach. The other thing that happens is that some women develop hypotension during the pregnancy. And again, we'd start them on the drugs that I've just suggested. When you get to preeclampsia and eclampsia, it's not for junior doctors, it's a bit of a ride at times, but the real treatment is delivery as quickly as possible. People use magnesium, all manner of things. Basically, you want to get the baby out as soon as the baby is viable and minimise the risk to the mother. It's a decision made by gynaecology, much better than I can do. So we get them to the last phase of the pregnancy, and I'll hand it over.
Great. Well, I think all of those topics have been really interesting. And hopefully, our listeners will agree, what kind of pearls of wisdom or nuggets of knowledge would you like to give to any kind of junior doctor or registrar who's working on a medical ward or an acute receiving unit when they see someone with hypertension?
Well, I think the key thing, which is very interesting, you asked me that question is don't believe the patient comes back to your patients presenting in AMD or in the acute medical unit with hypertension, and they say, Well, I'm taking my drugs, probably they're not. And there's pretty good evidence now because there are urine screens for adherence testing, not only in hypertension, but in other chronic diseases such as respiratory or rheumatology. And for reasons we don't fully understand these patients stopped taking their therapy. And there are data out there for blood pressure management, suggesting that in unselected outpatients from blood pressure clinics, such as my own 25% of the patients are either not taking all the drugs or only taking some of the drugs. And of course, that is the reason why their blood pressure is poorly controlled. So think non compliance first, rather than secondary causes of blood pressure or regard non compliance is your primary secondary cause. The second point is you hear this term resistant hypertension, this is a definition, someone who's on three antihypertensive agents of which one may be a diuretic, and still, their blood pressure's not controlled. Almost certainly these patients are not taking their therapy. In our clinic, we are pretty confident now we can control anyone's blood pressure, provided they're prepared to take the tablets. And we've got adherence testing data to support what I've just said, it's not arrogance, it's a fact. Just because we now have the evidence to back it up. So think non compliance. Second, do not get nervous when you see a patient with a blood pressure of 180. No evidence of target organ damage. It's either because they've got a white coat effect, or they're anxious, or they're not taking their therapy, but they're not going to come to any harm over the next few weeks. And you can take your time, refer them back to primary care, or get a specialist to come and see them, but they're not going to drop dead on your watch. Or if they do, it'll be bad luck.
That's great. Well, thank you so much for taking your time to speak to us today. I think that was a really useful and insightful overview on hypertension. So thank you very much.