GPs have signed off a series of sweeping referral restrictions by NHS managers that will bar smokers and overweight patients from being referred for surgery, as PCTs across the country bring in new cost-saving restrictions.
…set me wondering if there was some sort of structural problem with medicine.
Only a couple of hundred years ago, a great many injuries and diseases could not be treated, and most people didn’t live very long. But as more and more life-threatening injuries and diseases have become curable or treatable, and people have lived longer, it seems that instead of needing less medicine, we seem to need more and more of it. I began to wonder whether the better doctors got at curing things, the more of them were needed, and hence rationing came to be necessary.
After thinking a bit about what might happen in a human population as medicine improved, I decided to do what I so often do in these circumstances: I wrote a little computer simulation model.
In this model, a new cohort of 100 people (i.e. newborn babies) were added every year to a human population consisting of a set of such cohorts, and so the total population grew at this rate. Once I’d got that bit working, I then supposed that there was a 1 in 10 random chance of absolutely anybody having a nasty accident, or catching some bug, and dying. I didn’t suppose that there was any funny business called “ageing” or anything. All death was accidental. When these accidental deaths by injury/disease were added in, the population stopped growing, and instead stabilised at about 1000 persons, with an average age of about 9 years.
I then supposed that whenever anyone had a nasty accident, or caught some bug, they received medical treatment of varying effectiveness. Medical treatment could be 100% effective, or 0% effective, or anywhere in between. And I plotted the total number of medical treatments (both successful and unsuccessful) that were required per year against the success rate of the treatment -which ranged from 0% (completely ineffective) to 100% (complete cure every time). If the treatment was effective, patients lived on until their next mishap. And if it wasn’t effective, they died.
And this is the result I got:
So, as medical treatment improved, the number of medical treatments increased. In fact it grew exponentially. The better the treatment, the more of it was needed. And conversely, back when doctors couldn’t cure anything, there wasn’t much work for them to do, as all their patients died.
So it looked like improved medicine simply meant more and more medicine, as more and more treatments were needed. No wonder doctors were being rushed off their feet.
Except that, although the number of treatments grew exponentially with improving treatment success rates, so also did the total population. When medicine was all but useless, doctors were doing 100 (ineffective) treatments a year for a population of 1000 people. But when their treatments were 95% successful, they were treating 2000 people a year in a population that had risen to 20,000 persons. So the number of treatments needed per person remained constant at 1 treatment every 10 years. The need for medical treatment simply grew linearly with population, and so the numbers of doctors and hospitals grew linearly with population.
So doctors weren’t being rushed off their feet, trying to treat more and more people as their medicine improved. But the population increased, and people lived longer. In fact, in my little model, the mean age of the population when medical treatment was 95% effective was 193 years! And some individuals lasted a lot longer than that. But leaving that aside for the moment, it meant that when medicine was completely ineffective, doctors would have mostly been treating children of age 9 years. And when their medicine was 95% effective, they were mostly treating people aged almost 200 years old.
I then wondered what difference would be made if the rate at which people got sick/injured was varied. This would correspond to “healthy living” – not smoking, drinking, eating too much (or too little), avoiding doing risky things like walking up and down stairs, etc, etc. I could do this simply by changing the the chance of someone having a nasty accident from the 1 in 10 I’d initially set it as.
To my surprise I found it made no difference at all. Regardless of the rate at which people got sick/injured the overall pattern was the same. Even if people got sick/injured at half the rate, or twice the rate, the number of treatments needed stayed almost exactly the same. What did change was the population: doubling the injury rate halved the population.
So the conclusion of this little mathematical exercise was that, yes, when medical treatment was more successful, more of it was needed. But this was because the population had grown, and people were living longer. The amount of treatment per person needed stayed exactly the same. But also, it made no difference whether people lived “healthy lives” or not, avoiding risks. It didn’t reduce the amount of treatment needed.
In short, there shouldn’t be any need for rationing of medicine, and encouraging “healthy living” is pointless, because it doesn’t decrease the burden on the medical profession.
This is, of course, a very simple model. And it doesn’t accurately reflect the real world in a number of ways (e.g. not all injuries/diseases are fatal if untreated). And also I may have screwed up the logic somewhere in my little model (which I only wrote this afternoon).
All the same, I thought it came up with an interesting result. Can anyone else replicate it or improve on it?