Psoriasis (Part 1) - Head, Elbows, Knees and Toes

Now today, George and I are going to be talking about psoriasis, and what we should know about before we look to treat it, and this is the first of two podcasts on this very common condition, with its treatment being the subject of the second one in two weeks time. So do make a note to check that out. But, first of all George, I do think it's helpful to talk about the definition of psoriasis, because many people listening might not understand very clearly exactly what the condition is.

Psoriasis is a skin disorder which is chronic. In other words, it goes on and on. So if you have psoriasis, the chances are you may come back with it at a later stage in your life, even if it clears up. But I think it's important to say from the outset, it's non-infectious, it's not contagious and it's an inflammatory skin disorder. The skin is inflamed. And when you look at it, you typically have these well-defined, red areas of abnormal skin, which has a very typical silvery scale.

The scale easily falls off, but it gets air underneath it, which means that when you look at it, it has that sort of silvery look to it. So it's a chronic, non-infectious, inflammatory skin disorder with well-defined red plaques, is what doctors call them, and silvery scale. And I think many people listening will start to recognise that either on people they've seen themselves or even from the condition that they've got, which is maybe one of the reasons why they're listening.

But the cause, the epidemiology, if I can use that term, it's really interesting as to why someone with psoriasis should have, psoriasis, isn't it? Well, yes, it is one of the most common skin conditions, one of the most common conditions, that our society suffers with. So it is extremely common. And what advantage does that have? Why is it there? I think this is really quite fascinating. It's common in those societies, today, that in the past were affected by scarlet fever.

Psoriasis offers some protection against the bacteria that causes scarlet fever, the streptococcus, and we've just gone through a minor epidemic of that. The streptococcus appears to be coming a little bit more, vigorous and virulent in recent years. But in the past it was, talking 70 years ago, it was really frightening. It was pre-antibiotic era, and it killed a large number of people, a very large number of children. And in scarlet fever, your skin becomes bright red.

It can peel off, and if it's really severe, you can then start losing a lot of fluid, your blood volume drops. You don't perfuse important things like your liver and your kidneys, they start to fail, and you die. Well you can die rather, it's a nasty, dangerous illness, scarlet fever. And it's not as virulent today as it was 100 years ago. But if you've got a tendency to psoriasis, you're relatively protected.

Instead of getting red skin and skin peeling off, you get thickening of the skin and raising up, what doctors call hyperkeratosis, these plaques of psoriasis. And in particular, you get a pattern we call guttate psoriasis. From the Latin guttae, "a raindrop". It looks like you've got little raindrops of psoriasis all over your body. And that typically comes on a couple of weeks after encountering a streptococcal, a bad streptococcal infection.

So you don't die, you have an inconvenient skin rash. And that confers enormous advantage to you, and that probably accounts for why the genes persisted. If you look today where psoriasis occurs, it occurs in those societies where scarlet fever killed. So, for example, compare the North of China to the South. Psoriasis today is four times more common in the North than the South.

Looking at their records in the 19th century, scarlet fever was four times more common in the North of China than the South. Aborigines had no scarlet fever, they had no psoriasis until we brought our genes into their gene pool, and the same with Indians. So, it's very, very interesting looking at that relationship. So psoriasis does confer some advantages, more than that actually.

If you've got psoriasis, you harbour the bacteria in your throat, where it does you no harm, and you can then populate the next epidemic of scarlet fever, killing off your genetic competition; people who haven't got the advantage of having psoriasis. But the headline figures are, yeah, it affects roughly 2% of the world population, and that's about the prevalence in the UK. In the world, 125 million people with it.

It's much more common in white Americans who migrated to America from Scandinavian countries where scarlet fever was common, 4.6% in white Americans. Less than 1% of black Americans have psoriasis. And it affects men and women equally. Although it often starts in childhood, typically with that guttate pattern following a sore throat. Roughly a third of people first encounter, first have their psoriasis as a child or a young teenager. And genetics plays a huge role.

This is a multigene condition, where polygenic, in other words, isn't just one gene. It may be a combination of genes. But 40% of patients with psoriasis have a family history and the more members of your family there are, with psoriasis, the more likely you are to get psoriasis earlier, and the more severe it's going to be. But, there are over 60 genes, that, we wonder whether those might account for some of the different patterns of psoriasis we sometimes see.

Yeah, so it's much more complex than might initially appear and you'd think that although it is a complex condition, you'd think diagnosing it would be fairly straightforward. In other words, you'd rock up to your doctor surgery, they'd take a look at your skin patches and there you are. But one of the things I've learnt over too many years of treating patients with psoriasis, there are a huge range of possible presentations.

So it can make the diagnosis a little bit trickier than people might think so there are a number of patterns of psoriasis out there. The most common pattern, is called "chronic stable plaque psoriasis". And that classically affects the backs of the elbows and the fronts of the knees. Often on the body, on the buttocks and around the place, it can be quite severe and cover large areas of skin, and that's probably the most common.

The scalp is very commonly affected, probably about 4 out of 5 patients have involvement of their scalp and it's not necessarily visible because hair will cover that very effectively. But if you lift the hair up, you can see it just creeping just beyond the hair margin. So very, very common. It can affect the nails.

The nails can be really troublesome, and often you just get minor changes, like little holes drilled into them, we call that pitting, or the nail can lift off from the nail bed, which is quite unpleasant, with a lot of scale and thickening of the tissue underneath the nail. People don't recognise it, often miss flexural psoriasis.

It can go for the armpits and the groin and the buttock crease and under the breast in these sort of moist areas and can be a bit tricky there because it doesn't look quite the same as psoriasis elsewhere. It hasn't got that dry, scaly look. It just looks glazed, sharply demarcated as it typically is in the plaque psoriasis but without the scale it just looks shiny and glazed and can be often misdiagnosed there. And then there are other patterns too.

But I think the important thing is if you're seeing somebody with psoriasis is to look at them as holistically as you can. You need to find out about their family history. You need to think about any aggravating factors that might be going on that are driving it and then you look carefully and you feel the plaques. I think, as a doctor, it's so important to touch our patients, with their permission, wash our hands and then touch them.

Feel their plaques, because society generally is repelled by skin disease and patients with psoriasis often feel quite ostracised by that. And I think for a physician to be prepared to go straight in and feel their plaques, examine the nature of the scale, looking carefully at all the nails and asking about the flexures, feeling the scalp. I think that's so important and so that's part of my assessment there.

Of course, and you mentioned patients with skin conditions feeling, ostracised and this is perhaps greater than ever with people with psoriasis. Whenever I've given talks at conferences about psoriasis and mentioned the psychological impact of psoriasis, including some truly dreadful suicide statistics in the UK of people with psoriasis killing themselves simply because of the psychological impact of their psoriasis. You can usually hear a pin drop in the room as those facts sink in.

Now, regular listeners to this podcast will know that I don't talk about individual patients, often. But in this case, I am going to mention a particular patient. I have changed details so they can't be identified, and it was a long time ago. So I'm not breaking any confidences here. But the reason I would mention this one is that this completely altered how I viewed patients with psoriasis forever. In fact, it altered how I viewed patients with all skin conditions forever.

Which was a highly successful businessman, single man, late thirties, been having treatment for psoriasis pretty much for over a decade. Seen a lot of my colleagues, and eventually rocked up in front of my desk, I think more in desperation than anything. I was a senior partner in practice, and he thought that, well, I'll go and see, you know, the senior partner.

Patients sometimes think that because you're senior partner, you know more, which is untrue, but that's a psychological fact of what can sometimes happen. And he sat down and we were talking about psoriasis and how he was wanting to try and get to the bottom of this and then he promptly burst into tears on me. Which really took us, I think, both back.

He was a chap who tended to sort of keep his emotions to himself, and so we explored that, and going through quite a long consultation, into a nutshell, he said that he was just, desperately, desperately lonely. He could not be in a relationship and had not been in a relationship because of the impact of psoriasis and the shame he felt from it. He had not had physical contact.

He had not hugged someone for years because he was ashamed about his psoriasis and he was a single man because he could not bear anyone seeing him in the morning, hoovering the skin flakes out of his bed, and that's why he was single. And that really dropped the scales from my eyes and I really understood then the impact, psychologically, of skin conditions. We fortunately managed to get his psoriasis controlled, and better.

And a couple of years later I just happened to see him in passing and he was as happy as I've ever seen anyone, in a lovely relationship, and that has continued through to this day. But I think the point of that is that for some people with psoriasis, the physical impact of this visible condition absolutely pales, compared to the impact it does on their mental health, and I suspect you've had many similar stories.

I have, but that is a very lovely and powerful story, and I can understand how it would change my practice as well, for the better, I hope. Ah, it's so easy not to hear about the distress, somebody else is suffering. Humans have that extraordinary capacity to turn a blind ear to that sort of thing. And I think that shame, that word shame really resonates with me. Isn't that awful for him? What a lovely, lovely outcome.

And I think that in this modern world we live in, skin disease is something that people are repelled by, and particularly with young people who are using social media, where how they look is being noticed and commented on and criticised is so powerful. I think we need to be very, very alert to this. Because skin diseases are visible. It's often the first thing someone notices when they see you.

And we're wired to be repelled by physical deformities, and patients experience that all day, every day. So it's no surprise that skin diseases punch way above the objective severity when it comes to the impact on their life experience.

A study about 5 years ago showed that more than 4 out of 5 patients with psoriasis reported that they had experienced discrimination or humiliation because of their psoriasis, and almost a half reported it had adversely affected their personal relationships, especially intimate, as in your patient's case. So I think it's something we need to be very, very alert to.

Nowadays, we're increasingly talking about what we call the cumulative life course impairment, that a disease like psoriasis can cause. You can imagine how some loss of self-esteem because of your psoriasis and loss of confidence as a teenager can mean that you decide not to try to join a team or even remain in school to do your A-levels. And then underachievement at school means you underachieve after school. You don't get the further education opportunities.

Career options are limited and missed. And it has an increasing potential impact on relationships, which you may never want to embark on, like your man, or you do and they fail. And the consequences of what might to many just seem as a trivial skin condition, a bit of scale on the backs of your elbows and the fronts of your knees, can progress to have a devastating and lifelong impact. And I think we need to really wake up to that and recognise that this matters.

Yes, I cringe when I hear people say, "you've got a touch of psoriasis." It's like saying "you're a little bit pregnant." It's, you know, irrespective of the severity of the psoriasis, and this has been replicated in a number of studies looking at other conditions like eczema and acne. There is no direct link between how severe the skin condition is and how severe the psychological impacts. You can have a relatively mild skin disease and absolutely enormous, psychological impacts.

There is something that you just mentioned earlier and I just wanted to pick up on it. You said that psoriasis is an inflammatory condition, which might be an interesting statement to some people listening. Why did you make that point? Well, I stressed it, didn't I? Yeah. Chronic inflammation from whatever's driving it, whether it's arthritis or psoriasis, or even eczema. We now know even bad eczema, is bad for you. And it's particularly bad for our arteries. It causes hardening of the arteries.

So, it accelerates the rate at which that gets worse. So controlling inflammation, we recognise now, is so important. You cannot leave chronic low grade background inflammation. It will increase your risk of heart attacks and strokes. Psoriasis is also associated with central obesity, that's sort of fat tummies. And that's linked to accelerated heart disease and diabetes.

And, in fact, psoriasis is also associated with an increased risk of diabetes and the condition of the liver where you get fat deposits in the liver causing it to not work so well. So, non-alcoholic fatty liver disease and diabetes are other concerns.

These are very, very important for GPs and I think that if you have moderate or severe psoriasis, I think it's worth talking to your doctor about your overall risk for heart disease and asking if they can do what's called a QRISK, which is putting together your blood pressure, your cholesterol, whether you smoke or not, and so on. Putting all those together to give some sort of measure of how high your risk is for heart disease.

And taking that into the context of someone with chronic inflammation, it means that you might address some of those risk factors more aggressively. Yeah. Inflammation really matters. Yeah. I think anyone who's listening with psoriasis, will know from experience just how quickly their psoriasis can go from well-controlled to a significant flare. Almost to the point of being out of control when certain factors trigger it, almost like petrol on a fire.

So I sometimes say that, you know, well-controlled psoriasis hasn't gone away; it's just there like embers of a fire and then certain things can throw petrol on it. So I often think of the four S's when I'm looking at patients with psoriasis. There's potential triggers, although there are lots more, and you probably mentioned them. But things like, as you say, streptococcal infection, smoking, absolute, and we'll touch on this, a big no no, stress, and steroids. And those are my four.

I always sort of go down the list first, although there are some more on top of that. I love those four S's. It's so helpful, isn't it? Yep, so streptococcal infections. And interestingly, I mentioned that patients with psoriasis often harbour that bacteria in their throat and they have more sore throats. But the strep can be a sort of chronic sort of stimulus for more psoriasis. People have tried penicillin to try and eradicate it, but it doesn't seem to help. So that's not the answer.

But there's certainly that link. Yeah, smoking. Smoking does make psoriasis worse. But also, like psoriasis, it hardens the arteries. So you've got a double whammy there, really bad news. And it's also the driver for a very, very nasty, though not uncommon, fairly uncommon rather, pustular condition that occurs on the hands, or feet; can be very disabling. I haven't seen that in someone who's never smoked. So, an important message. If you've got psoriasis, you shouldn't be smoking.

Absolutely not. Stress, well we've already covered the fact that psoriasis is stressful, but stress seems to make psoriasis worse as well. So you're into a vicious cycle there. The worse your psoriasis, the more stressed you're going to feel, the more stressed you're going to feel, the more, it's going to be making the psoriasis worse and so on. So, not necessarily easy to address that but certainly being alert to the stresses in your life and see what you can do there.

Steroids, I don't like using steroids on their own, on the skin, in patients with psoriasis. I think that if I ever prescribe a steroid topically, for psoriasis, I'd want to use another agent to go alongside it. Because that can, particularly when you stop, withdraw the steroid, it can trigger a severe flare. And I've even seen terrible flares of psoriasis when people have been on steroids for something else.

Acute asthma, or whatever, and they've been on a steroid, is when you stop the steroid, things can suddenly go dramatically and very severely out of control, rarely putting the patient on intensive care. So I personally say don't use topical steroids on their own for psoriasis There are a lot of drugs that doctors can prescribe that can make psoriasis worse.

The two that you need to know about, I think, are lithium, which is used for bipolar disorders, so just be aware of that, and anti-malarials. So if you're going to a malaria zone, the classic, quinolines, things like, chloroquine and things, those will make psoriasis worse, and there are alternatives. But there's a list of things that can make psoriasis worse and worth talking to your doctor about those. I should have mentioned alcohol earlier.

Alcohol, along with smoking, it definitely makes psoriasis worse. And intriguingly, psoriasis is one of those skin conditions where if you have a tendency to psoriasis and you damage the skin, you can get psoriasis in the newly damaged skin, which is the last thing you need. So if you just had an operation, and you've got psoriasis, you can get psoriasis in the scar, or if you get sunburn, you can get psoriasis in the sunburn. So we're aware that it likes damaged skin.

And so we've got our patient, we've taken a good history from them. If someone goes along to their doctor, to talk about their psoriasis, what are the sort of things that they could expect their doctor to be talking about, when they're assessing them? Well, I'd suggest it'd be a good idea to take with you all the current treatments that you're using. And I'd include in that, any shampoos, any face products, what you're washing with, your soaps. I hope you're not using soap.

Your washing agents though. So everything that you're using, including things you buy over the counter that you're using on your skin. So take those with you and I'd like to think the doctor might want to have a look at those and see what you're using and see how much you're using, where you're using it. I'd hope that the doctor would allow you to tell them what's going on and what's in your mind and what you're worried about.

I hope that they'd sit back and allow you to have the space to put them in the picture, to put the doctor into the full picture, they know what's going on.

If you've got any joint trouble, joint pains, joint stiffness, joint swelling, significant low back pain and early morning stiffness in the back, which I think most of us do have to some extent, but if you've got significant joint trouble, for goodness sake, be sure to tell your doctor that you've got psoriasis and you're worried about your joints. That's a very, very important area of psoriasis management. It generally merits urgent referral to a joint specialist.

There's no reason why you couldn't download what's called the Dermatology Life Quality Index, the DLQI, and you can download that easily online, and it's a questionnaire, has 10 questions, each with the potential of a score up to three, so a maximum score is 30. And I would suggest it's not a bad idea, if you're going to see a doctor, just to fill out one of those, print it off at home and take it with you and say my DLQI currently is.

If your DLQI is less than 5, it's unlikely that the psoriasis is having much impact on your life. Between 5 and 10, I take it seriously and I know that we need to do something about this. If it was over 10, if we can't get it lower than that, that's a justification of going on to really super potent things like biologicals. So, we take a DLQI over 10 as having a massive impact on the patient's lifestyle. I've occasionally seen this in the 20s. So it's very useful.

It can also alert you to some of the things that psoriasis can do. So you may say, "oh, other people with psoriasis are having this problem. I might tell my doctor about that or alert them to that." So definitely do a DLQI yourself. And go prepared to be examined. I think if the doctor knows what they're doing, they're going to want to feel your skin.

They're going to want to look at your skin, they should be looking at your hair, and at your hair margins and at the very least, they need to ask you about the flexural areas. So they may want to look at your armpits and your groin, and at the crack between your buttocks, or under your breasts. And this is good practice. So go prepared to be examined. I think that's an important message there. I think that's really good overview and a nice little point to bring this little chat to a close.

So George and I do hope you found this chat, about this very common, but highly life impacting skin problem, interesting, and you found the overview helpful and even given you the confidence to go and speak to your doctor about it if you haven't already. Roger and I hope you'll join us again in two weeks time where we'll be discussing the management of psoriasis in a bit more detail. We'd also like to thank our sponsor, AproDerm®, for all their help in putting these Skin Deep podcasts together.

We couldn't have done it without them. So until then, it's goodbye from George. Goodbye. And as always, it's goodbye from me. Goodbye.