The Epidemic of Fake Disease

I've got my myocardial themed tea ready because today we're going to talk about fake disease we're living in the era of fake news after all so it's only fitting and I'm not talking about selfie itis or affluenza I mean things like cancer so what am I going on about well this episode is about when cancer isn't cancer [Music] have you ever thought about getting one of those full-body scams you know the kind a very emotive advert perhaps on the train with a grieving wife and children if only that dead fool had come in for our cancer screening service he'd still be with his family today they work on scare mongering and pretty much make it sound like it's almost your fault if you get some horrible disease because you simply weren't paying close enough attention to your health and that's why you should spend 99999 now I'm not gonna tell you what to do with your money but I'm certainly not going to spend any of my own on a well man checkup or full body scan and I'll try to explain why the concepts in this video are some of the hardest to grasp in the whole of medicine so I'm not going to try and cover too much in this video and I'm sure we can revisit things in future videos some of the things you'll hear will sound completely contradictory and counterintuitive we'll start with Kevin Hart who watches a news report about how many men his age are dropping down dead from heart disease he sees a documentary about a CT scan that can detect early narrowing of the arteries before you have any symptoms he pays handsomely for a cardiac CT scan which finds a 70% narrowing in a coronary artery which the reporting doctor calls a ticking time-bomb he undergoes the implantation of a stent which is a procedure where we insert a tiny metal tube about the diameter of the spring inside your biro but with much thinner metal unfortunately he suffers quite extensive bleeding in his right arm which gets very swollen and he has to stay in hospital for a couple of days and can't drive for a month but after all that he's okay next up we've got Mary melon a 45 year old woman who hears that breast screening saves lives she attends for mammography a government-run programs are paid for by taxes it's a very uncomfortable test but she soldiers through because she feels it's important and is shocked to hear an abnormality was found she has a biopsy which shows ductal carcinoma in situ a type of cancer she's got two young children she's terrified and opts to have a complete mastectomy along with an unpleasant course of chemotherapy she develops an infection of the surgical area it takes a while to heal and she's left with permanent swelling of her left arm but after all that she's okay so how do you think Kevin and Mary feel all right their operations had some complications but at the end of the day they're alive they feel like their lives have been saved their families are overjoyed their diseases were caught early they probably feel tremendous gratitude and are likely to recommend the tests to all their friends and family and who can blame them especially when the doctors themselves often reinforce this belief but is what they believe actually true in both cases we know that in fact the likely outcome of them undergoing those initial tests is that they've been harmed more than they've benefited we know that for stable asymptomatic patients like Kevin stent do not prolong life nor reduce the likelihood of having a heart attack and in fact I don't think anybody would put a stent in Kevin today but this scenario would have been very common a few years ago don't get me wrong for unstable patients people having chest pain people having heart attacks stents are life saving and one of the best therapies we have in medicine in fact but not for patients like Kevin for Mary the biopsy did show cancer but it's a cancer that might never have caused her any symptoms whatsoever and potentially she had a breast removed and developed this long-term arm swelling for no net gain if both of those last two paragraphs sound confusing don't worry just stay with if you have a pain and come to see me as your doctor and I send off a test that's called investigation that's me trying to find a cause for your symptoms but if you don't have any symptoms you feel completely fine like Kevin and Mary did and then I send off a test that's called screening screening is where we try to look for the signs of a problem before a patient has any symptoms however unfortunately screening is a very complicated topic and often one that's quite emotive as well and therefore difficult to discuss so today we're just going to talk about two concepts lead time bias and over diagnosis let's start with how we talk about disease prognosis you've all seen that cliched conversation in movies where the protagonist says dark be heist with me how long do I have and the doctor saw many replies you have only six months to live yes you probably don't watch as much Nigerian cinema as I do but you get the idea in reality it doesn't work like that because everybody's different in fact surveys of palliative care doctors who deal with the death more than anybody else show that even they are spectacularly bad at predicting when a person with an illness will die instead we talk about populations so we say if you take a hundred people with this particular cancer then in five years time eighty of them on average will be alive now this is a statistic called five-year survival which is used very commonly but it's misleading rudy giuliani some years ago was trying to explain why he felt American privatized health care was superior to the British National Health Service which is free at the point of access and he said I had prostate cancer five six years ago my chance of surviving prostate cancer and thank God I was cured a bit in the United States 82 percent my chance of surviving prostate cancer in England only forty four percent under socialized medicine now that sounds like a pretty clear demonstration that the aggressive screening program for prostate cancer in America has saved many many lives but the death rate from prostate cancer in the UK in the u.s. was pretty much identical so how can both statements be true let's say that this is the point at which prostate cancer causes symptoms and is diagnosed and here is when the average man dies when we hear 5-year survival rates have improved you descri nning we assume it's because people are dying later but actually it's because we're diagnosing them earlier if you diagnose someone here even though they're dying at the exact same time you've not helped them in any way their survival time from diagnosis is better simply because you've diagnosed them earlier this is lead time bias and it's frequently misused to show that screening works in fact the correlation coefficient between 5-year survival and death for the most common cancers was looked at and it was zero and that's really saying something there's no link between five-year survival and how many people are dying from a disease which is of course the thing that any sufferer cares about so we should just stop using five-year survival and focus on mortality it seems like common sense to think that earlier diagnosis equals earlier effective treatment and of course sometimes that is true but the big problem is is that our treatments are far from perfect and in fact a lot of them are harmful in themselves or the tests that we do after that initial test might be as well and another huge challenge is you're going to end up treating a lot of fake disease and by that I mean an abnormality that's been detected on the test that is not causing and would not cause that patient any problems whatsoever this is over diagnosis and it's becoming more and more common as our tester becoming more sensitive and we're able to pick up abnormalities that we would have never previously been able to detect here are five of the most common cancers in the US all of which are routinely screened for or being picked up as incidental findings and body scans you'll see that over the last forty years the number of cancers being diagnosed has gone up across the board but the lower lines deaths from those cancers have remained remarkably stable so either our treatments are getting better at exactly the same rate as the increase in cases or we're diagnosing things that aren't causing any harm aka fake disease in fact just last month a large and important trial was published looking at lung cancer screening now lung cancer is one of the most deadly diseases killing millions of people around the world and it's the kind of thing you really hope a screening program would work for but in response to the question does lung cancer screening save lives that answer was a clear no the patients who were screened and had their lung cancer diagnosed earlier had more scans more invasive tests and more treatments like chemotherapy but no difference in death rate on that point I want to briefly mention the Apple watch because I've made a couple of videos about it and make a little comparison here so in this trial patients at high risk smokers with greened for a deadly disease lung cancer and no benefit was found the Apple watch looks for atrial fibrillation which is a much less deadly disease than lung cancer and the people wearing the Apple watch on the whole are at a very low risk of atrial fibrillation so while I've made it clear that I think the potential for what we can do with the Apple watch is very exciting and it's a fantastic technology when I say that it's unlikely to save lives I'm normally met with complete incredulity okay here's another way to look at it this is adapted from H Gilbert Welsh's teaching on screening please do check the references below as I've put some extra reading there especially that of H Gilbert Welsh and Margaret mccartney - fantastic writers and - heroes of mine in this field which I really recommend let's say a cancerous process starts here some nasty genetic mutation or fault of cell division along the y-axis we have size of the cancer at a given size the cancer will cause symptoms to the patient and then at another size it will cause death the x axis is time and over on the right is where the patient dies of a non cancer cause so the time they would die if they never got cancer this is a fast growing cancer which causes death not long after its first noticed by the patient these are not picked up with screening normally as there's not much chance to catch them and as you might imagine they have a poor prognosis here we see a cancer growing at a medium rate it eventually will cause death earlier than the patient would have otherwise lived so this is the type of cancer you want to pick up with screening but there's another kind of cancer this is a very slow growing cancer which the patient dies with but not from and this is an important phrase in medicine if you look down a microscope the cells have all the hallmarks of cancer but it's not cancer in the way that you or I or society understands it this is cancer that isn't cancer at least not with a big see the classic example of this is prostate cancer which about half of older men have when they die of another cause and it's only detected on postmortem thyroid cancer rates in people who die of other causes is similar and yet types of cancer do this they just sit there Mary's ductal carcinoma and sit you might go in this group and some even regress in fact some people don't even call what Mary had a cancer even though on a cellular level it definitely is if your screening test identifies any of these that's over diagnosis disease from the Latin literally meaning without ease is not present if the pathology is not causing any symptoms nor adversely affecting the person's life so this is what I mean by fake disease treating these will not only not help the patient but may even harm them which is the one thing that doctors are definitely not supposed to do but of course when you're over on the left side of the graph it's impossible to predict the trajectory of which of those lines the cancer in question will follow so of course you end up treating all of them and patients with fake disease confuse the statistics like this if you have a hundred patients with the particular cancer in five years time 50% of them are alive that's a survival rate of 50% but with screening you may pick up another hundred who have fake disease and now you've got 200 patients to start with in five years time fifty are still dead you haven't prevented a single death but you can immediately claim that survival rate is now 75% because 150 patients are still alive at five years the great success in these ducks like a quack videos I often talk about the power of anecdote normally is a problematic thing for example if I show you a meta-analysis of coagulated casein genuflection and its effect on self-reported TB ephemeral intra-articular pain you'll probably glaze over but if I slap some America's Got Talent sob story and music on in the background and tell you about my crippling knee pain that was ignored for years by the uncaring heartless medical profession until I built a church made of cheese and knelt at its cheddar altar every night until my knee pain was miraculously cured now you're interested oh god of cheese hear my prayer so I thought I'd join in with anecdote of my own particularly because I'm aware that my attitude is completely opposite to celebrities you'll see on TV acting as patrons for various charities saying that their disease or cancer was caught just in the nick of time so make sure you get screened and by the way I'm not attacking those celebrities at all kudos to them for doing a good thing if screening is misunderstood by many in the medical profession then it's unfair to expect anything different from non medics incident loma is the name given to an unexpected finding on a scan in a tissue or an organ that was normally not the intended target of the test as the number of radiology tests we're requesting is increasing as the scans themselves are getting more and more sensitive the rate of incidentalomas is soaring the most commonly requested tests things like CT scans of the chest and abdomen or something that I report a cardiac MRI scan account for Low's of these incident filaments cardiac MRI is now the number two source of incidentalomas in the u.s. cardiac MRI is where we use an MRI machine to scan the heart but because the heart is in the middle of the chest you get all the surrounding structures so top of the kidneys liver lungs and the thyroid which is just here in the neck I was reporting the scan of a 42 year old woman who I'll call Sophie who initially presented with a very non whirring innocent-sounding history of palpitation fluttering heart and her heart was completely normal on the scan but I spotted something in her thyroid gland which as I'm not a specialist I referred on and this led to what's called a cascade of care she had blood tests she had further scans she had a biopsy of the thyroid gland which is where we stick a needle into the neck and that was inconclusive so she had to have the test repeated it showed some concerning changes for cancer so now she's got the scary label of thyroid cancer when she only went in to see her GP in the first place for some fluttering heartbeats which have now completely resolved she's told she needs an operation which she undergoes she has part of her thyroid gland removed but unfortunately her recurrent laryngeal nerve which supplies the voice box is damaged Sophie then has radioactive iodine treatment as part of the ongoing therapy of her thyroid cancer which is generally quite safe but has one major side effect now Sophie is a singer she'd had a pretty exciting life touring the world as a backup singer for various groups and had never planned on settling down but recently she met a guy and they had settled down and then decided to have kids and she knew full well that the age of 42 it was pretty late but for the last year her fiance and her had been trying but then when this came along the thing with radioactive iodine is that you mustn't get pregnant add to that her voice never recovered from the operation which obviously as a singer was devastating Thurid became underactive so she has to take replacement medications and she'll be on those for life with all this going on not only the radioactive iodine but the whole stress of the situation she lost a year and she feels that that was her last chance to try to get pregnant I could have picked a very black-and-white story where an incident Lomo was picked up that was definitely not harmful and the patient underwent a litany of tests and horrendous complications and believe me every medic knows a story like that but I chose this one because it's actually had an impact on me I don't know if the thyroid cancer would have killed Sophie perhaps it would perhaps it was for the best that she went through all of that in spite of the complications I'll never have the answer to whether that thyroid cancer should have come out or not and neither will Sophie and that uncertainty unfortunately is central to everything we do in medicine our tests are not perfect they produce false positives but even when the results are genuine it's not always entirely clear what we do with that information I can only apologize to you as the public that you get such conflicting messages about things like screening and as I said at the beginning of this video I am NOT suggesting to anybody watching not to have a screening test but hopefully now you can make a more informed decision I'm on my way to work back to the grinder for a few magical days in a company of some of the best educational youtubers out there imbibing wisdom just basking in the aura of their end youtuber magnificence people like Wendover real-life floor coos kazar CGP grey Ali Abdullah science with Katy knowing better and many more because it was YouTube edge akan a meeting of all those educational youtubers and lots of others from around the globe and due to some bizarre administrative caca I found myself hosting the whole event along with the fantastic Madi mote and I told the joke that philip Detmer of puskás are described as the greatest joke ever told at a youtube event two dates and probably forevermore but I guess you had to be there enough showing off the reason I'm bringing this up is because you'll find all of the aforementioned educational youtubers on nebula which is a streaming service offered to you for free thanks to the sponsors of this video curiosity stream if you sign up for curiosity stream using the link below and the code mid-life you can access to all of their thousands of high-quality documentaries for only two dollars 99 only $19.99 a year they have hope loads of medical content but I hope this video demonstrates that to apply medical knowledge well one also needs to understand statistics and logic things medics and in fact October's aren't taught very well so I would recommend the joy of series which has episodes on logic statistics chance and data presented by people like Hannah fry and Jim al-khalili nebula nebula is a streaming platform where all those aforementioned educational creators Superstars and me can test out our new material without worrying about the YouTube algorithm screwing us over my demonetized videos can still find an audience there along with nebula originals like one of my favorite channels up and items argument against reality existential crises have never been this much fun so that's curiosity stream comm slash midlife with the code med life for all this educational documentary goodness for only 20 bucks a year honestly that is a really good deal as I always say I'd rather you take advantage of what the sponsors are offering instead of giving me money because I'll just spend it on expanding my cheddar altar to finally accommodate a sluicing place where living sacrificial offerings can spill their blood in devotion to his cheesy magnificence

Channel: Medlife Crisis

Views: 634,692

Rating: 4.9361005 out of 5

Keywords: Medlife Crisis, Medicine, Science, Education, Comedy, Doctor, Cardiology, Medical School, Screening, If It Ducks Like A Quack, Cancer, coronary artery disease, CAC, Cardiac CT, Breast cancer, Prostate cancer, Health, Overdiagnosis, Lead time bias, Pseudodisease

Id: yNzQ_sLGIuA

Length: 20min 57sec (1257 seconds)

Published: Tue Feb 25 2020