04-08-2025
Our immune systems react when we see sick people
Norman Swan: So have you got little techniques, Preeya, for remembering stuff?
Preeya Alexander: I think I meant to say yes to this, but I don't. I've got quite a good memory, if I'm being honest, I have quite a good memory for some things.
Norman Swan: What things?
Preeya Alexander: Anything related to my children that's really important in the parenting space, or medicine, I can remember. But if you ask me, 'Did we read this book? Have we seen this movie? Did we go to this restaurant?' I'm shocking.
Norman Swan: Right. And presumably you remember our arguments and things like that?
Preeya Alexander: Oh, of course, I remember all our…I'll never forget those, Norman, never.
Norman Swan: And did you have little tricks when you were studying for your medical exams?
Preeya Alexander: Of course, acronyms and all sorts of things. You must have too?
Norman Swan: Yeah, just repetition and so on. But I do sometimes use this thing, which we're going to talk about in today's Health Report , called mental time travel. Turns out I actually do use that sometimes where I just can't remember something, and I just take myself back to when it occurred to see if I can put the bits back together again. And often I'll come up against a bit that is just a block, and I'll have to phone somebody up and say, 'Remember that thing 20 years ago?' And they say, 'What the bloody hell are you talking about?'
Preeya Alexander: This is very similar to a Robert De Niro movie that I saw recently, so it's all probably linked.
Norman Swan: Well, Robert De Niro will not be on today's Health Report . I'm Norman Swan on Gadigal land.
Preeya Alexander: And I'm Preeya Alexander on Wurundjeri land.
Norman Swan: Also on the show, vaping rates are dropping in young people, which is great news, but for those who do vape, there are serious risks, and the habit could spread to smoking.
Preeya Alexander: Artificial intelligence apps called scribes are being widely used to listen into your medical consults. Are you being told, and do you need to consent?
Norman Swan: It's an interesting problem there with some potential good attached to it.
Preeya Alexander: In the news, there has been the national report card come out for the mental health state of the nation for 2024, it's just been published.
Norman Swan: And just before we go on, this is from the National Mental Health Commission, and the purpose of the National Health Commission is really to keep the system honest and to reflect back to itself.
Preeya Alexander: And what it's found and reported on is really quite devastating in many instances. I'm going to read you a couple of the stats. In people aged 16 to 24, the prevalence of mental health disorders has increased, the sense of control people have felt has declined. Signs of financial stress are higher, particularly amongst women. There's been no improvement in loneliness. And more people are delaying seeing a mental health professional due to cost.
Norman Swan: So just some of those…I mean, given the Mental Health Commission kind of looks at the system, some of those are out of the health system, loneliness and so on, financial stress, but it goes to government as a whole because those are social and economic settings.
Preeya Alexander: And we're spending more on mental health. So in 2021 we were spending $491 per person. It's now gone up to $501. Despite that, in public mental healthcare the clinical outcomes and patient experiences have not improved. So the system really is in dire straits, and the report itself acknowledges that there are some deficiencies here, and you don't really get a true glimpse into community management when it comes to psychological and mental healthcare. But this is a multi-system issue, this is government, this is prevention, and there's no quick fix here, Norman.
Norman Swan: No, but the solutions have been on the table. So one of the problems here is we spend billions of dollars on a better access scheme to clinical psychologists, and while they do a good job with people with relatively mild mental health issues, when the complexity rises and people get more and more serious mental health problems, which is really what the Commission is reporting on, those individual psychologists, individual GPs, individual psychiatrists, even if you can get in to see a psychologist and a psychiatrist, it becomes less effective. So we need to be funding team care and community-based care so that people are actually being treated where they live, in communities that are supportive, and our system is not designed for that.
Preeya Alexander: So this report card is all in the context of we've already spoken about psychiatrists in New South Wales, the public system had a mass exodus, lots of resignations due to under-staffing and workforce issues. People will have also seen in the news that Australia's largest private hospital provider, Ramsay, have just announced that they're going to be closing 17 of their 20 psychology clinics across Australia.
Norman Swan: That's the private sector.
Preeya Alexander: That's right, but it tells us there's a problem. And I have to say, for people on the ground, it really is very difficult to access the care you need, particularly if you're trying to go through the public system. So this report card doesn't surprise me. This is what I think lots of us are seeing in the consulting room.
Norman Swan: And disturbing data being released from the South Australian cancer registry (and you'd have to assume that there's nothing particularly special about South Australia, it could be reflected in other cancer registries) where they've looked at 40 years of data, and it's now published in a peer reviewed paper, looking at survivorship in cancer. And what they found in there is that if you were diagnosed with colorectal cancer as your first cancer, so that's bowel cancer basically, there was a much higher risk of you developing a second primary cancer. So not a metastasis, not a spread of that cancer, but a new cancer. So it was prostate, it was even a second colorectal cancer, lung cancer, breast, a leukaemia, or a leukaemia-like cancer.
Going back to that Four Corners I did two or three weeks ago at the beginning of July which looked at younger adults under 50, but particularly 30-year-olds developing a range of cancers, including bowel cancer, the rate of second primary cancers was 50% higher in younger adults. So everybody with colorectal cancer had an increased risk, but it was particularly pronounced in younger adults, which brings us back to what was going on in the environment.
Now, some of this might have been genetic, like the so-called Lynch syndrome, where you can get a variety of cancers associated with bowel cancer and it puts you at risk of various others. But the implication here is it goes beyond that to environmental causes, such as ultra-processed foods, the microbiome, changes to the immune system and so on. So there are lots of things happening with cancer instance in Australia and around the world which we need to have a look at.
Preeya Alexander: And I think this illustrates that for colorectal cancer, where you've got younger people being diagnosed, better cure rates, more people surviving, which is wonderful, we really need to be onto this secondary cancer risk and doing adequate surveillance for patients.
Norman Swan: And what a psychological burden, if you like; you've just got over one and this sword of Damocles is hanging over your head about another. Look, it has to be said that the numbers are low, but the risk is growing.
Preeya Alexander: Now to an interesting paper that's been published in Nature Neuroscience , that maybe the brain triggers the immune system when we see someone who looks very sick. I thought this really validated a lot of things that I feel happen in my body, Norman. This study came out of Switzerland. They had 248 well people who wore virtual reality headsets and they were exposed to different looking faces, avatars, humans. And what they tried to test is if the brain senses a threat, like a pathogen, someone who looks really sick, and they showed people avatars who had rashes, who were coughing, essentially what I see in the clinic all the time. The question was does the brain kickstart something in the immune system to prime it, to get it to function more effectively?
They've done lots of different measures, they've looked at MRIs, at blood tests, they've looked at reaction times to see whether or not the fight or flight response is engaged. And what they found is that in the people who had been exposed to the sick avatars, they had higher levels of innate lymphoid cells, which are basically white cells that you have in your immune system, and the levels were similar to the group who had had a flu vaccine but not been exposed to a sick avatar. And they also had heightened alertness, suggesting that there's a smoke detector system; the brain detects a threat, the pathogens, someone looking really sick, and it actually does set off a bit of a cascade in the immune system.
Norman Swan: And this is the first barrier of the immune system, the so-called innate immune system, which is inflammation that you hear everybody talking about at the moment, which promotes ageing and so on, it's more than just the immune system being activated. And interestingly, you talked in the Mental Health Commission report about people losing a sense of control, and what happens when you lose a sense of control is that your brain goes on the alert, and research done at Rockefeller University in New York and other places have shown that this leads to changes in the immune system, that the innate immune system gets fired up as well, because the person perceives a threat, because they feel out of control of their lives. So we shouldn't be surprised about this. The mind and the body are a single entity, and we're fully integrated.
Preeya Alexander: We are.
