S5 E2: Idiopathic intracranial hypertension

Idiopathic intercranial hypertension

Series 5, episode 2

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Transcript

00:00:00 Welcome to the Heads Up podcast, brought to you by the National Migraine Centre, the only UK charity treating headache and migraine. Visit our website to book your appointment with a world-class headache doctor, wherever you are in the UK. There is no need for a referral. You can refer yourself. Our headache specialist doctors are looking forward to helping you soon.
00:00:33 Dr Katy Munro
So welcome to this episode of Heads Up podcast and today we’re going to be talking about a relatively rare headache condition called idiopathic intracranial hypertension and I know when I started as a headache specialist, this was one of the things that I learned a great deal more about, but I’m delighted to welcome today two real experts in the field of studying this particular condition, Professor Alex Sinclair and Miss Susan Mollan. So welcome to both of you and you both work in Birmingham. I think that’s right, isn’t it?
00:01:10 Prof Alex Sinclair
That’s right. Katy. Yes, I’m over at the University of Birmingham for some of the week and then over at University Hospitals Birmingham the other half of the week.
00:01:17 Miss Susan Mollan
And I work full-time at University Hospitals Birmingham.
00:01:21 Dr Katy Munro
And I know the two of you have been involved in a great deal of research about idiopathic intracranial hypertension. We’ll talk about some of the things that have been discovered that can be helpful later in the episode. But first of all, can you just say a little bit why you got involved in it? What was it that made you feel that this was an area that needed more study, Alex?
00:01:47 Prof Alex Sinclair
Oh, that’s a good question. And actually it probably takes me back to my junior doctor years, Katy. So I remember when I was back then a junior SHO and just starting to get interested in neurology and I was sent over to see some of the neurology referrals on a Monday morning that had accrued over the weekend. And I went to one of the far-flung outlying wards of the hospital in Birmingham that I was then working in to find a very frightened young lady who was telling me that she could only count fingers in front of her eyes that morning. But on Friday she’d only been able to see the hands waving in front of her eyes. And so her vision had declined really rapidly over about a week to a really terrible level of visual perception, and she’d had bad headaches for about 6 months, and she was a typical young girl of about 24, and she was typically overweight and she’d come into casualty on Friday and had that typical work up of a brain image which was normal. And then had a lumbar puncture with a high pressure and then been put on an outlying ward for neurology to sort out several days later.
And so in that ensuing time her vision had really gone off. And I remember thinking, this is an unusual condition where young people go blind so quickly, potentially. And then when I read up on it as a junior doctor, I realised that we knew very little about it. And so I sort of sparked a bit of an interest and started seeing more and more cases.
00:03:04 Dr Katy Munro
So it’s often a signature patient that leads us into those kind of pathways, isn’t it? What about you, Susan? How did you get interested in it?
00:03:15 Miss Susan Mollan
Yeah, I’m very similar. So as a junior doctor, as a fellow, I joined a group of neuro-ophthalmologists, and they all had full clinics of patients with idiopathic endocrineal hypertension. And I just thought it’s such a strange condition where it’s really unfair where patients may be overweight or obese and get this very curious condition where they get raised brain pressure. I think the other side of one of the reasons why Alex and I partnered together was not only the research, but actually as ophthalmologists, as eye doctors, we’re really bad at looking after headache and we see a lot of headache patients. So that for me was like actually can we do something about this rather than just say, oh, go see your GP or find a neurologist? So.
00:04:02 Dr Katy Munro
Interesting. So the two of you do a joint clinic, I believe, is that right?
00:04:07 Miss Susan Mollan
That’s right, yes.
00:04:07 Dr Katy Munro
Yeah. So really good to have both sides of the aspects of neurology and the neuro-ophthalmology working together. Are there any other disciplines that come into your team?
00:04:19 Miss Susan Mollan
Yeah. So we’re very fortunate, actually. Well, one of the reasons is we’ve got a very large service, but at the moment we’ve got some specialist nurses and also some senior orthoptists that are doing extended roles in our clinic. It’s also a very popular clinic for our international fellows because we’re known quite well for this condition. And because we’ve been working together for some time and we’ve had the structure from research I think it’s just a very popular clinic with both the patients, the doctors and the nurses.
00:04:52 Prof Alex Sinclair
I think the other thing that’s interesting for me as a career working in a joint clinic with an ophthalmologist and coming from my roots as a headache doctor primarily, you know, headache neurologist, is that actually there’s so many headache conditions where there are visual phenomena going on or where you’re worried about the visual axis. So actually, there’s so much overlap for many of our patients. Even if it’s not IIH we kind of share thoughts and diagnosis from quite a few other patients that come our way. So I can think of quite a few examples that have kind of swapped between the ophthalmology and the headache clinics.
00:05:23 Dr Katy Munro
It is something in the National Migraine Centre that we often have patients who say, oh, I thought it was my eyes giving me the headache, so I had my eyes tested and yeah, I think it’s very interesting to explore that more, isn’t it? And also that sort of visual sensitivity, the light sensitivity we hear about all the time. But just to divine the term, so idiopathic intracranial hypertension or IIH, can we take that apart a bit because idiopathic, so that means we don’t quite know what causes it, am I right?
00:05:57 Prof Alex Sinclair
Yeah, that’s right.
00:06:03 Miss Susan Mollan
So I think the more we delve into it, the more I think actually we’ve learnt a lot along the way and it’s almost like it’s totally becoming less idiopathic. And I guess we’ll talk about those bits in a minute.
00:06:14 Dr Katy Munro
So we may have to change name.
00:06:18 Prof Alex Sinclair
Eventually, I hope maybe we will be able to know enough about the condition to no longer call it idiopathic, but I think one of the useful phrases of being idiopathic means that we’re setting it aside from other causes of known raised brain pressure. So we always have to distinguish idiopathic intracranial hypertension from secondary causes of raised brain pressure. Such as being caused by drugs. Or if you had a brain bleed and you had a high red cell count in your spinal fluid, or if you had Guillain-Barré syndrome or malignant meningitis. So there are lots of secondary causes of raised brain pressure, which we differentiate by giving this very specific condition, the term idiopathic. But yes, I hope that within our lifetime we might be able to change that.
00:07:00 Miss Susan Mollan
And I think that sometimes when we say idiopathic, it makes some people think that we don’t know what the risk factors are. And for our very typical disease it’s a very sensitive issue that the major risk factor is weight gain and rapid weight gain within the months or even the year leading up to diagnosis. And so it’s tricky to talk about that.
00:07:28 Prof Alex Sinclair
Yeah, there’s a lot of weight stigma in our clinics and maybe we’ll talk a bit more about that, but that’s something that we have to really think very cognizantly about and really work out how we can address that so people feel comfortable with us talking if they want to talk about weight aspects of the condition.
But just picking also up on what Miss Mollan was saying, you know that word idiopathic also doesn’t mean that we don’t know what the condition is. We do know what this condition is. It’s very specific. It has very specific diagnostic criteria. It’s just the full underlying cause is not yet defined.
00:08:00 Dr Katy Munro
So can you say a bit more about the diagnostic criteria because that covers the intracranial and the hypertension bit. I mean, some of my patients will think, oh, hypertension, isn’t that blood pressure? But of course it just means raised pressure. And the reason it’s intracranial is because it’s raised CSF – cerebral spinal fluid – pressure, isn’t it?
00:08:22 Miss Susan Mollan
Yeah, so absolutely right. We’ve got a clearly defined diagnostic criteria which has sort of grown through the years when we’ve had new medical discoveries such as brain imaging. So all of our patients with typical IIH must have papilloedema at diagnosis. That’s bilateral eye nerve swelling from raised intracranial pressure. They need to have a normal neurological examination, but that can include if you have raised brain pressure. you might have double vision from a sixth nerve palsy. That’s the only thing that you’re allowed to have on neurological examination. Then you need to have normal brain imaging, but you’re allowed to have signs of raised intracranial pressure signs on your brain scans.
Very importantly, we must have venography and that’s a scan to look at the blood vessels, the venous drainage within the brain. Because venous sinus thrombosis, which can cause significant morbidity and death, can happen rarely. It’s obviously had a little bit more press recently when in the pandemic, but all patients with papilloedema need venous sinus thrombosis excluded. And then we move forward after looking at the scans and making sure they look OK to perform a lumbar puncture and that’s where we record the opening pressure and we also take a sample of the CSF, the brain fluid, and send it to the lab and make sure that there’s no strange things within that fluid and you need to meet all those criteria to have a diagnosis of IIH. And it is sometimes challenging for people that come along because they can have raised brain pressure from other causes but not have papilloedema and other conditions. So in some respects we’re quite fortunate that we have these diagnostic criteria that we can really apply it nicely to our patients.
00:10:28 Dr Katy Munro
Just if you could just explain a bit more so if people are listening and thinking what would a sixth nerve palsy feel like or look like for example to a GP. If you went to the GP with headaches and they were looking for it, what would they be looking for?
00:10:44 Miss Susan Mollan
Well, Katy, that’s a really good question because a lot of people can get a bit of blurring and a bit of confusion of their visual symptoms. And in some respects, some people say that’s double, but actually, they’re not having a sixth nerve palsy. So sixth nerve palsy is when you’re not able to move your eye out. And it can happen in one eye or the other eye. So it gets to the middle and it really can’t go any further. And you see frank doubling of the image particularly in distance. So sometimes my patients will have no problems with double vision reading a book or on their phone, but actually when they’re looking down the road at the bus or something like that they will see it and I’m sure we’re going to really delve into these kind of crossover visual symptoms. It’s absolutely definite and I would say within our clinic we have very few patients that present with a sixth nerve palsy. I mean, I can think of maybe one person this year and we’ve got a very large clinic. So it’s something our patients might say if we ask them, oh, do you have double and they say yes, but they can have other reasons why they might have an imbalance in their muscle system in their eyes, but not a sixth nerve palsy.
00:12:01 Dr Katy Munro
Right. So what are the most common symptoms that people present with?
00:12:07 Prof Alex Sinclair
Well, probably the most common symptom by far, I guess of great relevance to the title of your podcast, is headache, so the overwhelming majority, around 90 to 95%, will present with headache. And these headaches may be episodic initially, and then become more frequent and more frequent and more severe, typically in the sort of six months building up prior to a diagnosis. But in some people longer.
And then as the condition becomes more chronic, the headaches often become more daily and have a sort of background severity, with superimposed really severe spikes of headache attacks. So headache is the first and most common thing that people usually present with, and it’s often that that eventually takes them to seek medical help. But as Miss Mollan was mentioning, there’s other symptoms as well. So transient visual observations occur in about 60 to 70%. Particularly when they have severe disease and these are black-outs or grey-outs of the vision, can be in one eye or the other, so it could be in one eye or two eyes, typically lasts for a couple of seconds and it might become more frequent and they might become more prolonged as the disease becomes more severe.
And then the other symptoms that we hear a lot about are slightly more non-specific ones. So, for example, if you look at things like back pain, neck pain, dizziness, these occur in sort of 40 to 50% of patients. So quite non-specific symptoms.
And then visual loss as Miss Mollan was mentioning is common, sort of non-specific visual symptoms in about 1/3 to 40%. And then I think one of the most important aspects that is very new to be acknowledged really is the cognitive fogging or cognitive loss, which we now very much recognise in IIH patients.
It’s probably there to some degree in all patients that have significantly raised brain pressure, but whether that will come to the fore and be mentioned at a consultation that may or may not happen. And recently we’ve had some really nice research showing that it’s quite multifactorial and lots of things kind of interplay as to why you might have cognitive fogging. From the actual raised brain pressure to other things like the headache attacks impairing your cognition, low mood and depression, co-existing obstructive sleep apnoea and the medications you’re on. So cognitive fogging is a sort of new kid on the block but increasingly recognised.
00:14:30 Miss Susan Mollan
I think the thing that’s interesting is we share a lot of the symptoms with migraine patients. So for example, I think one in four patients with migraine can get pulsatile tinnitus and some of our patients a predominant symptom for them can be pulsatile tinnitus, so sometimes unpicking what’s true to IIH and what’s migraine like is quite a challenge for us.
00:14:56 Dr Katy Munro
I’m guessing that a lot of patients, because migraine is so common, a lot of patients may already have a diagnosis of migraine, which is a correct diagnosis of migraine, but then develop IIH on top of that.
00:15:12 Prof Alex Sinclair
Yeah, absolutely. And that’s a really very frequent situation, possibly in as many as up to 50% of patients diagnosed with IIH will have had pre-existing childhood or pre-existing diagnosis of migraine.
00:15:22 Prof Alex Sinclair
And they very likely may have a migrainous relative, as you see in a normal migraneur, and that all impacts really on how we think the trajectory of their headaches will go after their IIH has been diagnosed and whether they’ll resolve their headaches, whether they may continue when their brain pressure settles.
For those patients that have migraine often may have migraine aura, which then needs to be distinguished from any visual phenomena that’s coming as a result of raised brain pressure. So it’s that very careful history taking and pulling out, whether it’s migraine aura, visual blurring. or a visual observation from IIH.
00:15:55 Dr Katy Munro
So the transient visual obscurations that you are talking about aren’t really quite the same as the things that I hear about when patients describing migraine aura when it tends to be a sort of a central disturbance of vision that’s spreading outwards towards the periphery, maybe zigzags, flashing lights.
00:16:13 Dr Katy Munro
The transient visual obscuration is more of a kind of fleeting change. Is that right?
00:16:18 Miss Susan Mollan
That’s absolutely correct, Katy. So the transient visual observations are very, very well defined. And just as Prof Sinclair says, this is a greying out or a blacking out of vision for seconds. I mean, often when my patients first get it, they don’t actually realise that was it there, was it not there?
And as we’ve kind of underlined a lot of our patients, if they’re getting worse, and the disease is getting worse and the brain pressures going up and there’s significant compression of the optic nerve. They get them more frequently so often, they’ll say, well, it used to be when I bent down or when I got up in the morning or I changed my posture. But now I’m just sitting, you know, watching television. And suddenly my vision and one eye goes.
It’s often unusual to get bilateral transient visual obscurations at exactly the same time. That would be uncharacteristic of the condition. So I think for some patients it’s a way they used their symptoms to tell them if the disease is getting worse.
00:17:24 Prof Alex Sinclair
Just again, that crossover between headache and migraine patients and IIH will be to say that not only in our clinics are we picking apart these transient visual obscurations and sixth nerve palsy and visual blurring from IIH and differentiating from the migraine aura vision phenomena. But the other thing in our clinics, it’s very common and gives you visual phenomena is the postural hypotension or vasovagal symptoms when you feel light-heated and you can again get some very temporary blacking or darkening of your vision, which can come and go. So these phenomena and these visual phenomena are very frightening to patients and it can be very helpful just to spend the time and unpick it and actually say, well, actually it isn’t your IIH getting worse, this is postural hypertension or actually now this is migraine attack giving you this and to then give the right treatment for the right type of visual phenomena.
00:18:09 Dr Katy Munro
Is there a postural element? So with patients who have had, say, a CSF leak or some sort of low CSF pressure for whatever reason, they tend to say oh I feel fine when I lie down, but then when I stand up after a while it gets worse because that CSF is draining down. So is it the opposite with IIH? Do they tend to prefer to stand up?
00:18:36 Prof Alex Sinclair
Katy, that’s really interesting. And when I first was taught about raised intracranial pressure headaches, whether that was IIH or brain tumour or anything else, you’re quite right. We were taught the opposite, weren’t we, we were taught that lying down would make your headache worse.
I can, you know, having seen these patients now for over a decade and these really busy clinics where we really carefully phenotype the headaches in multiple patients, every clinic, I think it’s highly unusual and the only time I really see it is informal and really severe cases who are really in extremis.
For the vast, vast majority, my clinical experience would say that the headaches are migraine-like and that is now very much borne out in the modern literature, where between sort of 65 to 85 to 90% of the headache phenomena types are migraine-like.
So we don’t really see this postural phenomena very much in its true form. All I can really say is the typical thing is that when you lie down, a headache may feel more comfortable, like it does in migraine. And we do sometimes find that the patients don’t want to sleep absolutely flat overnight because their brain pressure may go up during the night hours and be worse in the morning. But it’s not that kind of rapid change that we see as in with a CSF leak.
00:20:00 Miss Susan Mollan
And I think as well when we think about those low-pressure patients that we see because although we do an IIH clinic, we often get sent people with other problems with their brain pressure.
If they’ve had the condition for quite some time, you get a real blunting of your headache type, so they really lose that postural component.
00:20:12 Dr Katy Munro
Yeah, I would say that’s what I’ve heard as well from patients with CSF leak.
So we’ve been talking about the sort of symptoms that people might notice, and it sounds as if because of their overlap between migraine and IIH, it may take a long time for these patients to actually pitch up in your clinics. How? What’s the sort of average time from patients starting to have symptoms, or is that a bit of how long is a piece of string question?
00:20:43 Miss Susan Mollan
I think that’s really interesting because when we go back with our patients they often assign a completely different time point to when we would have suggested, so if they had a bit of visual blurring and their headaches are starting to escalate, we might say that’s the time that the brain pressure started to increase and say somebody that had a prior history of migraine. But often we don’t. We’re really lucky in the United Kingdom that we have a National Health Service. We’ve done some work comparing our patients with patients in America and they appeared to have much more of a delay in being seen by an expert clinic. So I think because of our healthcare system I don’t think there’s much delay in diagnosis. I think every healthcare system has a problem with misdiagnosis. And you know, picking out somebody that has had a prior history of migraine has an exacerbation of their migraine, we always teach that you must check for a papilloedema and those exacerbations of migraine.
Because everybody’s kind of entitled to get this condition. So I’m not sure that we see that that’s a significant issue, but there’s another issue as well with interpreting what papilloedema, and elevation of disc. And whether it’s what we say is true, papilloedema from raised brain pressure, or whether it’s another eye sign that’s causing the person examining your eyes to say that isn’t just textbook normal.
00:22:18 Prof Alex Sinclair
Yeah, absolutely. I was just going to reflect a little bit also on the last two years. So the COVID pandemic has really though I think has altered when patients present to us and we in fact published after the first lockdown the real problems we had with the late diagnosis at that point, so patients had much more difficulty accessing clinics everywhere and including IIH clinics.
We had the Association of British Neurologists who advised not to examine the back of the eyes during the first lockdown because there was the worry about COVID transmission. We had reduced patients turning up to be seen, and that’s still to an extent going on. And then we had the problems that we’ve now become much more, I think, accepting of that when people are locked down and at home and isolated, timetabling and eating habits and lifestyle changes and all the patients gained weight, so coming out of lockdowns, we saw a lot of patients with delayed diagnosis much presenting with much more extremism and with much more severe cases. So we’ve got an interesting journey as we start to blend face to face with telephone and video consultations and trying to draw that balance of making sure we do examine and think of IIH, even though now almost the majority of the headache consultations are virtual.
00:23:32 Dr Katy Munro
That’s one of the challenges for us at the National Migraine Centre has been having to go virtual because of not being able to have our clinic as a charity, and so we advise patients to get an optician check. Because opticians have great equipment these days, how good do you think that is? I mean, is it? Do you get a lot of referrals from opticians who’ve picked up papilloedema or suspicious about papilloedema?
00:24:00 Prof Alex Sinclair
Yeah. I mean, maybe I’ll start and hand over to Miss Mollan, but certainly a huge cohort of what we see comes from the opticians and I wish in a way we could work more closely and have these conversations with them. It’s hard to find because there’s so many different private providers to actually link up. There are national organisations for the neuro-orthopters, but certainly a lot of patients are coming through and they’re doing a great job at spotting early papilloedema and also through the tool of using OCT scanning, so that’s been really, really helpful to identify early disease. And I similarly in my headache clinic would advise patients to get the back of their eye checked at least once a year. Miss Mollan, what do you think about the high street opticians?
00:24:36 Miss Susan Mollan
Yeah, so I really do believe that they have fantastic resources. They all have these imaging platforms called OCT pretty much in every high street store now. I think the difficulty for us as ophthalmologists — because I actually keep these patients out of our joint clinic. Otherwise we’d never see any of our patients — is that there’s just so many people with what I call funny looking discs and it doesn’t mean that they’re abnormal. It just means they could be tilted or they’re short sighted. And so I would urge patients that if they do go to the optician, the optician says, oh, I think you need to be checked out by the hospital. Just go and have it checked out because for the majority of people, I would send away maybe 90% of patients and there’s really probably only about one in 10 or even less than that that actually have a problem that requires either investigation or treatment.
And there’s a very well-known case that went through the High Court with an optometrist who had, sorry, it was an optician, who had been examining and having difficulty examining a child and they put in and had some photographs taken of the back of the eye, and in fact they hadn’t been able to review the pictures and unfortunately that young child had raised intracranial pressure. That saw floodgates of lots of patients coming to the hospital eye services and while that’s not particularly an issue we’re not set up for that kind of, you know, almost like a screening programme of which we’ve not given them the right tools. And one of the pieces of work that we’re very passionate about in Birmingham is trying to develop those sort of clinical management decision tools, you know, based on imaging, so that our High Street opticians and our eye casualty and emergency room doctor are able to have something that guides them. It gives them a little bit more certainty rather than just sending every patient through to the hospital.
00:26:52 Dr Katy Munro
Am I right in thinking that OCT uses light in the way that ultrasound uses sound waves so it’s a non-X-ray, non-radiation-based technique to look at the back of the eye?
00:27:06 Miss Susan Mollan
Yeah, so it uses a scanning laser ophthalmoscope, absolutely completely non-invasive, very quick and very accurate. So it’s not necessarily the technology, the technology’s there. It’s really the expertise and you know, we’re very fortunate in Birmingham because I spend nearly two days just looking at papilloedema and discs so over a course of a decade you get very good experience and it’s trying to distil down some of that more senior experience that we have in our eye clinics and be able to have that accessible for people.
00:27:44 Prof Alex Sinclair
That really makes me sort of come to mind about the problems that we also have with misdiagnosis and you’ve alluded to it already, Miss Mollan, but the scanning that happens in the community is fantastic and it does identify cases and as Miss Mollan says, there can be a tendency for over-referral, but you know, safety check occurs.
But on the other side of that Miss Mollan mentions experience and that it is needed to have that high level of neuro-ophthalmology experience to be able to review the photographs, review on the slit lamp or to review the OCT imaging to determine if it truly is papilloedema. And we know very well from the literature that about 40% of the patients sent to our clinic as diagnosed with IIH don’t have IIH. It’s all due to the inaccurate sort of interpretation of the back of the eye, so that interpretation of the back of the eye is absolutely key. And I think I can’t emphasise enough how important your neuro-ophthalmology colleagues are in helping to do that.
00:28:39 Dr Katy Munro
So the next question is who gets IIH? So what kind of patient is it? A male, female, young, old, who? Who’s your typical patient? And are there atypical patients?
00:28:52 Prof Alex Sinclair
Yeah. Wonderful. So yeah, the typical patient, I guess is easier to describe. So the typical patient is the idiopathic patient and that is tending to be a lady, a female who is in her child-rearing years. So between puberty and menopause or that the condition can continue after menopause. And it tends to be associated with increased weight and with those who have a diagnosis of obesity with a body mass index greater than 30.
It is very rarely found in men, so I can think on a couple of hands the cases that truly have an idiopathic intracranial hypertension in men that have come through and that’s reflected in the literature in men, they very often have a secondary cause if you look for it. And so they are atypical and we have to investigate them very thoroughly.
Children. So young paediatric cases pre-puberty are very more heterogenic, very unusual. Very often secondary case causes and sort of behave in a very different way. But we then do see that similar pattern in young women post-puberty, particularly associated again with weight gain at puberty, and they get a very similar condition to the adult women with IIH. So adolescent and adult IIH is very similar, whereas that very young paediatric population is very different and the men are very different.
00:30:12 Miss Susan Mollan
And I think running through to those atypical cases, there are patients that don’t have that real risk factor of weight gain. And so within our clinic, we really choose that cut-off round about a BMI of about 30 because we’ve nicely shown in case control studies that that’s where the disease incidence takes off. And so if we have somebody that hasn’t had a history of weight gain and has the lower BMI, we’re really looking for those more atypical causes. And I think at the moment, with most diseases, you have a sort of umbrella and at one side we’ve kind of got the true paediatric disease, the major disease, and then at the either end of the spectrum are those more atypical patients.
00:31:02 Dr Katy Munro
So once you have diagnosed, so you’ve had the symptoms, you’ve obviously had to have a raised lumbar puncture pressure and you would normally have done some scans. So we talked about looking for venous sinus thrombosis and various scans. So what next for the patient? What would you then advise if a patient’s got that diagnosis?
00:31:29 Miss Susan Mollan
So we were part of the international consensus guidelines for idiopathic intracranial hypertension and we were able to survey neurologists, ophthalmologists and neurosurgeons in the UK with international peer review on this document and really what we came down to was splitting into those patients who were worried about their vision and might need surgical intervention on one side of which it’s only about 7% of our patients.
And so, overwhelmingly, the majority of our typical patients would then be on the medical management route. And what we agreed and we had patient representation on it and the multidisciplinary team on that guideline will say, well, we’ve got to say weight management for all. Because we know that the biggest risk is weight gain and we know nicely now from the first Birmingham weight loss study, but also our bariatric surgery trial now that actually if patients have appropriate weight management within the setting of a managed weight management programme, they can put their disease into remission.
And so it was really weight management as a first key and then the second key is really over to Professor Sinclair’s expertise and appropriately managing the headache.
00:32:50 Prof Alex Sinclair
Yeah, thank you. I just wanted to also just come back on one other aspect about managing weight gain and we tend to say in the guidelines if you have a diagnosis of obesity with a BMI over 30, we certainly advise about lifestyle measures and helping to lose weight. And I just wanted to talk a little bit about how that’s done because often in the clinic it can be very upsetting for patients if it’s not done in a sympathetic way. And I think I’ve learnt a lot from my colleagues who are specialists in endocrinology and obesity, about the stigma around talking about obesity in a consultation, about whether it even should be spoken about. But if you do, one of the approaches that they’ve always recommended to me would be to say to the patient, you know, would you mind if we talked about something sensitive? Could we talk about your weight and to get permission to engage in that conversation before you go in that direction.
And then to also remember that as you know, as neurologists and ophthalmologists, we’re not experts in weight management advice. There’s so many new things coming out. There’s new science coming out about what is driving obesity. There are new treatments coming out, both surgical and medical.
So I very much ask permission to talk about how it might be related to the condition and say now do you need some help here because I think the emphasis now is not on telling patients to go away and sort this out, but on saying, you know, this is a really hard and really chronic disease. Obesity is now known by the World Health Organisation as a disease. It relapses and remits throughout life. And would you like some help with our knowledge and approaches to how to manage this and where should we start: in the community, through your GP, or through weight management services in the hospital? So we don’t tend to be obesity specialists, but we try and talk about things in a sensitive way and signpost on correct avenues for evidence-based care.
And also to say that it doesn’t have to be a BMI over 30. You might find somebody who’s had a lower BMI, but they’ve gained weight rapidly, so they might have gone from, say, a BMI of 16 up to, say 24 or something like that. Then that could still be very relevant and important for their condition. So it’s a bit of discussion with the patient.
00:34:50 Miss Susan Mollan
We also find those associated conditions that Professor Sinclair was talking about earlier, so we will always do an obstructive sleep apnoea screen, preferably with the Berlin OSA screening and I think probably about 35% of our patients will then be referred to respiratory physicians for their screen and investigation of that. And it’s really important because we know that obstructive sleep apnoea not only impacts the headache, but can also impact the papilloedema and can confer worse visual outcomes.
And the other thing we’ll do is if the patients are very fresh to our clinic and haven’t come through casualty, we’ll always check their full blood count to make sure they’re not anaemic. Because about 10% of our patients have anaemia and for some of those patients, all you need to correct is the anaemia, so you know we’re not behind the door by actually talking about transfusion rather than giving somebody, say iron supplementation depending on where their haemoglobin is and how they’ve presented.
00:36:00 Dr Katy Munro
That’s really interesting. I’m guessing also with the weight that you’re mentioning that there’s also comorbidities of things like polycystic ovary syndrome or even diabetes. And you know, we know that generally, the world is getting larger and so is that making the incidence of IIH more common, as people do put on weight?
00:36:25 Prof Alex Sinclair
Yes. So that’s a really important aspect and something that we’re very interested in in Birmingham. So there’s two aspects there. There is no doubt that the incidence of IIH is going from what used to be a relatively rare condition to something that is becoming more and more common. We’ve seen the condition increase by 350% in the last decade, in line with the obesity epidemic in women. So there is absolutely a relationship, and Miss Mollan was mentioning that as the BMI goes above 30, the rates of IIH go up and up and up. And it’s almost as an exponential curve, showing the incidence rates related to BMI. So we are undoubtedly seeing more cases of IIH in parts of the world that have higher rates of obesity and even in parts of the UK that have higher rates of obesity.
But that sort of brings us round to talking about the co-morbidity of polycystic ovarian syndrome, which is certainly there. But also all the other adverse medical complications that can occur as a result of obesity, and we did some work looking at whether things like cardiovascular disease, risk of stroke, risk of heart attacks, and risk of pre-diabetes and diabetes was increased in IIH.
And actually what we found was that even compared to those patients that were matched for their body mass index, i.e. matched for obesity, they had a much higher rate. So IIH patients have a two-fold increased risk of cardiovascular disease on top of that, that’s due to their obesity. So they do seem to have a lot of flavours of what we would call a metabolic disease driving their condition and likely driving these adverse complications in the future.
00:37:58 Dr Katy Munro
I was really interested to read – I was looking at the study that you did on bariatric surgery versus community-based weight reduction programmes. I think there are several, aren’t there – Weight Watchers. Slimming World, Rosemary Conley?
And how do patients feel about having bariatric surgery and how available is it? Is it something that you can get? I mean for the results of the study, it looked as if it was definitely something that we should be thinking about.
00:38:31 Miss Susan Mollan
Yeah. So you know we were very excited to report those results because it showed a fantastic reduction in intracranial pressure and disease remission that followed out a year and two years and that’s ongoing. And it was actually a really popular study with our IIH patients because they were patients that have had the disease for more than a year, that came into that trial. And so you know we talked a little bit about healthcare systems earlier in the podcast. And you know, we have a National Health Service and that means that certain services are limited and if we look at our colleagues in Europe, they have much wider access to bariatric surgery pathways. And so I think what doctors can do for our patients is really advocate for them. We’ve discovered this unique signal in the fact that they have adverse cardiovascular risk over and above obesity and our patients do very well with the surgery. So it is also a pathway to get to surgery. So not everybody ends up with bariatric surgery in the end. So these weight management tiers are within NHS England and really trying to access them for our patients.
But there’s also a sort of caveat to that, because they’re very busy clinics and have a very structured pathway. If patients don’t engage really actively with them, unfortunately they will be discharged back to their general practitioner. So it’s a bit more of a partnership of making sure that if there’s barriers to access to care that we’re able to address those for our patients.
00:40:18 Dr Katy Munro
Going on to just talk a little bit about medication. So I know as seeing patients with migraine, we have a range of preventative headache medications. And so I wonder, some of the ones that we prescribe for migraine make people put on weight and others make people lose weight. So are there any of those that are useful in IIH?
00:40:42 Miss Susan Mollan
So I think that’s an absolutely fantastic observation and that’s really what we’ve found down in our clinic. We want to avoid those headache medications that may precipitate weight gain in young people such as beta blockers and tricyclics. We’ve also got to be thoughtful that a lot of our patients turn up with mental health conditions. So sometimes we need to avoid drugs that are going to adversely affect their mood. And so we definitely go for options that are more sort of side effect friendly. And I was very surprised when I started in Birmingham with Professor Sinclair as to the headache medicines that you borrowed from so many other conditions. You know, so actually the options for headache used to be quite limited, but now with Botox for chronic migraine and the new CGRP therapies, we’ve done quite a nice little bit of work around those and how they’ve really made an impact to our chronic patients. So that’s talking really about when patients have sort of daily or more chronic migraine-like headaches. Obviously, we always wait until the pressure’s coming down. We don’t like to treat our patients off the bat with headache medicines. And that’s partly because the patients are in an unstable window, we’re just starting to get to know them. We need to know whether the pressure is going up or what it’s doing. So we actually wait until the eyes are in a safe position before we start headache preventative medication.
It also is another helpful thing to not start it off the bat, because if you try say, a certain triptan and the patients have very high pressure, the patient’s going to say to you, well actually that didn’t work. But actually when the pressure settles, it might be a very effective triptan for their exacerbations on all of their headaches. And we’d be advocating for episodic patients that they have a triptan as per NICE guidance along with simple analgesia and an antiemetic and only moving towards headache prevention if they have it more chronically. But I don’t know, Professor Sinclair, if you’ve anything more to add on there?
00:43:01 Prof Alex Sinclair
Yeah, that’s it. I mean I guess my emphasis is it is important to treat headache in IIH. I think for a long time it wasn’t even treated, it was just acknowledged that it was there. And then the next step in actually managing the headache was not really a common practice. So I think it’s really important to address that aspect. It is extremely debilitating for patients. It is really one of the main reasons why these often young women can’t get back to work and can’t continue to manage their family as they’d like to. So headache is a really significant disability for patients.
And so actively engaging in managing it is really key. So as Miss Mollan was saying, we do have a number of treatments that we use once they get to the sort of more migrainous stage. So we often call that a persistent post-IIH headache. That situation where the papilloedema has settled, the brain pressure has often settled, yet headaches may remain, particularly in a prior migraineur. And there we are very much more aggressive about making sure we prescribe triptans as appropriate for the attacks and then preventatives as appropriate. And yes, of course the CGRP is opening up a whole new world for these patients, which is wonderful. But also to remember that medication overuse is really common. About a third have medication overuse. And actually, that’s important really early on. So even in those hot new patients do have the time, if possible to talk about trying to keep off opiates and be cognizant of the problems down the road if they get onto a lot of painkillers and how that can perpetuate headaches and give background headaches. So it’s really I think, an integral part of the consultation.
00:44:32 Miss Susan Mollan
And then obviously when we’ve got those very hot patients, it’s that consideration of should we be treating the patient with acetazolamide and we know from the IIH treatment trial that they showed a significant difference in the mean deviation of the visual field. So that’s one parameter of the visual field. And these patients were all very new patients. But for us in the UK, the level of the medicine that was used in the IIH TT is actually very high. So it’s four grammes in a daily divided dose. And it’s just not a terribly nice drug. It gives people active side effects of paraesthesia, tingling in their hands and their feet and around their mouth. It alters their taste and can make them feel quite nauseous. And that has some other more serious side effects in some rare instances. And so we do offer our patient that medicine. Often they come to us and they’ve actually already tried it and they don’t like it.
If they can manage to get past about two-three weeks, sometimes those side effects really settle down. And here that starts that a little bit of a sort of a, say quagmire, because I’m from Northern Ireland. If the patient’s on the little dose, a lot of doctors continue on a little bit of a dose and so if somebody’s on 250 maybe once or twice a day, I’m not sure that’s really impacting their brain pressure as much as it should be.
So we’d advocate if they’re on a very low dose there’s probably not much point. So we need to work our patients up and in our clinic typically they’ll be on a dose up to two grammes in a daily divided dose and we don’t use it for long. So one of the things we’re passionate about is using it at the right time and making sure you take the patient off that medicine, that they don’t accumulate lots of medicines moving forward. I think it can be very useful in a selected portion of patients, but what we’re aiming for in the long-term is disease remission through weight management.
00:46:39 Dr Katy Munro
That’s a medication I think GPs would be more familiar with from being asked about it for altitude sickness, but of course using that in a much lower dose, I think it’s 250 once, twice a day for something like that and it has mixed results, but listeners may have come across that from their travels. Back in the day when we could travel more easily.
00:46:59 Prof Alex Sinclair
More easily, absolutely. And then the other one that we often see prescribed is topiramate, in IIH. I’m in IIH and of course you know both acetazolamide both, topiramate and all the other drugs are used off-licence. None of them have a licenced indication for IIH so we’re using them off-licence. And topiramate hasn’t got any randomised control trial evidence, it’s open label evidence, and I think we often think about topiramate for three reasons. One reason is it has in some patients a weight-loss effect which can be helpful. Second reason is it has some anti-migraine properties which are well evidenced which we know about. And thirdly, we know that it has some actions again as to work as a diuretic to reduce brain fluid secretion. So it has a potential to reduce intracranial pressure. And actually interestingly, we ran some animal studies to compare some of these off-licenced drugs and to see which one out-performed the other when given very acutely and we actually saw that topiramate was the only one that significantly in the short-term reduced brain pressure and sort of beat as it were acetazolamide. But that was over short-term dosing in an animal model.
But I think the question is still very much out there about some of the other drugs that we sometimes try in IIH. For example, furosemide has really come back to looking at some data that was in animals actually in cats in the 1980s where it was given at tremendously high levels. And on that basis, we have used it in some patients. So we haven’t really got a very strong evidence base of drugs. The only trial that’s been through proper randomised control trials, as Miss Mollan said, is acetazolamide. So the Cochrane Review has very much concluded to date that there’s insufficient evidence of efficacy of these drugs.
00:48:35 Dr Katy Munro
So how excited are you both about the prospect of anti-CGRP drugs that may potentially be changing? I’ve certainly seen a lot of patients with chronic migraine who have been just so thrilled, but the problem they come across then is accessing this on the NHS because it’s an expensive treatment and there’s a lot of local protocols to get access to it.
00:49:00 Miss Susan Mollan
We’ve been very fortunate that we were able to run the only study that’s been done in IIH using erenumab and there are 55 of our patients that commenced erenumab. And I have to say it was life-changing. There were very few patients that didn’t tolerate it at all, and so it has revolutionised our clinic and those patients did meet national criteria because they’ve tried a number of different other headache preventative medications.
And I think you can write quite a strong case in IIH for those patients, for those medicines that have either caused weight gain in the past in our patients or have the potential to cause weight gain.
00:49:45 Prof Alex Sinclair
Absolutely. I mean, we really are very unkeen to prescribe pizotifen which you know previously was used to treat anorexia. So we certainly don’t want to use that because it’s known to give weight gain. Same problem with, you know, beta blockers cause weight gain, they can exacerbate depression and co-morbid depression and anxiety is really common in these patients as well. And some of them will already be on a tricyclic or another antidepressant. So you quite quickly often get through to finding drugs that aren’t going to do harm to your patients, then moving on to some of the more sophisticated second-tier headache preventatives. And similarly, we’re also very keen on developing new headaches to treat IIH per se.
00:50:26 Dr Katy Munro
So one of the questions I was going to ask you because I know a number of GPs listen to this podcast. What do you think is the role of GPs in managing IIH? Does it need the specialists such as the two of you, or do you feel that your role is more in diagnosis and making a management plan then GPS need to get involved in carrying that through?
00:50:48 Miss Susan Mollan
I think that’s an absolute partnership because we’re dealing with a chronic metabolic disease here. And so my expertise obviously is in the eyes and Professor Sinclair’s in the headache and we can totally recommend the best course of action with the headache medicines. But all those other things we’ve been talking about – the co-morbid mental health issues – our patients actually often need that sort of wonderful listening ear and co-ordination of care to make sure that they have had their obstructive sleep apnoea testing and follow up with those. We also are dealing with a disease where there’s a large portion of our patients who are socially deprived. So they often access care through those sort of, what we’d say, are slightly more inappropriate ways of turning up to casualty in exacerbation of headache.
So apart from the partnership, it’s also engagement with these patients and at every opportunity making sure that if they have missed appointments in the hospitals, kick them out, that you get them back in because that’s the best chance that we’ll get their disease into remission.
00:51:58 Prof Alex Sinclair
Yeah. I also just wanted to mention about the important links we have with primary care in discussing contraception as well. There’s been a lot of, I think, miscommunication or previous data that’s now been sort of turned around about contraception and IIH. So really I think a lot of contraception is stopped when IIH is first diagnosed, and that doesn’t need to happen. So patients with IIH can remain on contraceptives. There is not a contraindication to being on contraceptives. Historically, 30 years plus ago when we had very high oestrogen level contraceptive pills, there were some anecdotal reports of IIH developing in patients on a high-dose oestrogen pill. But you know we very, very rarely see that. I can’t think in the last 10 years or so that I have seen a single case that I actually think has been induced by an oral contraceptive pill.
But I think far greater harm comes from the withdrawal and the withholding of contraceptives and then unplanned pregnancies and fear from these poor girls about what’s going to happen because they can’t use a contraceptive. So I very much advocate talking about the contraceptives and putting them back on. Obviously, you need to bear in mind if they have co-morbid migraine and they have migraine with aura. That’s another thing you might want to consider, not using a combined oral contraceptive. But also just to say that you know, it’s very common that our patients get pregnant, of course, and very many then get pregnant and go on to have very healthy, happy little babies with very normal outcomes from their pregnancy and the vast majority will have normal vaginal delivery. And again, that’s something that it’s, I think important to talk about with patients because it’s an area of fear and a bit of uncertainty.
00:53:32 Dr Katy Munro
That leads very nicely onto my next question, which was about family history. Is this a condition which runs in families? Is there a genetic element or is this purely down to environmental or factors within the woman’s life?
00:53:48 Miss Susan Mollan
I think that’s a really good question that we get asked a lot in our clinic and with our experience, it’s not a typically genetic condition that if your parents have it, you’re going to have it. There’s a lot of things around the social side and other things that we’ll probably find some small association in the way that we’re built like you do say in other conditions, but it’s not typically an inherited condition.
00:54:18 Dr Katy Munro
And so what’s the prognosis for people who have a diagnosis of IIH?
00:54:23 Miss Susan Mollan
Historically, I think a lot of our patients remained in clinic and didn’t have appropriate headache management and disease remission. And so the prognosis is if the patients have the support, they’re able to put the disease into remission and if they’re able to do that actually manage long-term without much problem with the disease. And it’s a relatively young disease is what I was going to say, so we’re really at the cusp of being able to understand how to manage it appropriately, so our patients don’t relapse in 10 and 15 years’ time. So I would say for the majority of people, the prognosis with good management is good in our patients who have a site-threatening disease. I think again if we get hold of those patients appropriately and get them to the right surgical team, they too can have reversal of their visual loss and do very well. So it is about access to care and meeting the right clinicians at the right time.
00:55:32 Prof Alex Sinclair
Yeah, I mean absolutely. It’s only like we said earlier, about 7% that will go on to have to have emergency surgical procedures to save vision. So for the vast majority, for 93%, this is going to be medically managed with lifestyle and medications. And actually something that surprised me over the time that I’ve been seeing patients is that some patients will go into remission and you think you’re sort of there, but then they will often relapse again. So I think I can be less certain about giving a prognosis, if it will last this many years and go away, because actually as we see these patients for more and more years now, we see them coming back and relapsing over time. So I think it is a chronic relapsing condition that comes and goes, often mediated through weight or other factors that we don’t yet know about and certainly the headache aspects seem to be very chronic for many patients, but very much during the COVID pandemic and we weren’t able to follow up patients as we wanted to we did see patients relapsing and it would have been very, very difficult if we’d not been able to continue to follow those patients up because some of them had very significant relapses of disease. So yes, a good prognosis if managed correctly, but I don’t think many patients can leave clinic for good and never relapse.
00:56:41 Dr Katy Munro
Do people who’ve had COVID infections who have a diagnosis of IIH get worsening headaches more than other people? Because I know it’s something that people with COVID infections get headaches anyway. Sometimes quite migrainous headaches where they’ve not had migraine before, and sometimes just an exacerbation of their migraine headaches.
00:57:04 Prof Alex Sinclair
No, it’s a great question, Katy. I don’t think we really know enough. I mean over the last couple of years, we’ve seen quite a lot of interaction between COVID and IIH. So I spoke about the difficulties of accessing care. We still certainly saw patients who were presenting that looked like IIH but actually had a venous sinus thrombosis and that was secondary to COVID infection.
And then of course, we had the worries about occasionally seeing very rarely a post-COVID vaccination thrombosis which could also potentially come through our clinic as presenting with raised brain pressure. But in terms of headache prognosis, I suspect that the headaches post-COVID are very much similar in IIH as they may be in anybody else.
00:57:46 Dr Katy Munro
I think it’s wonderful to hear of the teamwork and the expertise from both of you and your extended team. An awful lot of really high-quality research is being done in Birmingham so I think that’s very exciting for anybody with that diagnosis. I was going to ask you, are there any support groups or any resources you would flag up to patients?
00:58:08 Miss Susan Mollan
Absolutely, Katy. So I was going to say if anybody is listening today and they think they want more support or they want to find out more, IIH.org.uk is a fantastic website with lots of different information and it’s quite heavily supported by ourselves in Birmingham, but also researchers in London and other places. And as an international resource, it’s probably number one. There’s a couple of other organisations in Australia and in America, but I think our, I say our patient group, I mean the UK’s patient group is fantastic and that’s really thanks to all the trustees that work for free in that charity and are absolutely passionate about supporting their patients.
00:58:55 Dr Katy Munro
We’ll definitely put links to IIH.org.uk in the podcast blurb so that people can easily find that. So yeah, once again, thank you so much.
00:59:04 Prof Alex Sinclair
I must say thank you, Katy, it’s been a pleasure to come and talk with you.
00:59:10 Dr Katy Munro
That’s lovely. Thank you so much.
00:59:13 You’ve been listening to the Heads Up podcast. If you want more information or have any comments, e-mail us on info@nationalmigrainecentre.org.uk. Till next time.