The way we shop, do our banking, watch TV and listen to music is unrecognisable from 30 years ago – yet as a doctor, the way I do tests, treat patients and predict their outcomes is stuck in the 1990s when I started out at medical school.
Healthcare throughout the world is very much still analogue service in a digital world. So while the programmes that Netflix suggests and the products recommended by Amazon are personalised to you, when it comes to you as a patient, everything we do is based on looking after Mr and Mrs Average – in other words, 95 per cent of the population.
For instance, like all doctors, I’ll compare blood results from my patient with the general population and then give a treatment based on how the average person with that condition responds to that treatment, warning my patient about the side-effects experienced by the average person.
For the past 30 years, we’ve been waiting for the promised breakthrough in ‘personalised’ and ‘precision’ medicine, where a patient is treated as an individual and so truly benefits from the advances so prevalent in virtually every other aspect of our lives.
For example, with personalised medicine, instead of using generic reference ranges for blood tests, we’d look at your unique baseline and compare your results against this.
This could be happening sooner than we think, with research just published in the journal Nature showing the potential of this personalised approach – and, in fact, it’s something we can all start to try ourselves (but more on that later).
Why does this matter? Take the patient I recently saw in A&E, who had a number of symptoms including lethargy.
His blood tests showed he had a haemoglobin level (the amount of red blood cells) of 139g/L – around average for the population (135-180g/L for men), and so I reassured him that the results were normal.
Like all doctors, I’ll compare blood results from my patient with the general population, writes DR ROB GALLOWAY
But that just tells me his results are within the range of results found in the middle of 95 per cent of the population – not what’s normal for him. But because they were normal for the population, we told him everything was fine.
But what if his haemoglobin level used to be 150? His result now might have been the first indication of the start of kidney disease or undiagnosed bowel cancer, causing small amounts of blood loss. That’s what we mean by ‘personalised’ medicine.
Precision medicine takes it one step further. It uses cutting-edge technology, such as genetic testing and AI-driven diagnostics, to predict, prevent and treat diseases in a way that is specific for you. It is the difference between giving everyone the same old medicine versus tailoring a treatment for your body.
I remember a patient in his 30s who came to A&E with chest pains a few years ago.
As with standard medical practice, before doing any tests, I took an educated guess at how likely he was to have a heart attack and then interpreted the test result accordingly. His ECG (which tracks heart activity) didn’t look 100 per cent normal but was not concerning and his blood tests were fine.
After examining him, and from his description of the chest pain, as well as him not having known risk factors such as high blood pressure, I thought he was at a low risk of a heart attack and discharged him.
Sadly, a few hours later, he died after a heart attack that I did not – and could not – have predicted he was going to have.
If I’d been able to do the genetic tests that we now have (though not yet used routinely in clinical practice), I might have been able to spot he had genetic markers, such as the gene for lipoprotein A and apolipoprotein E, which raise your risk of a heart attack. And the ECG which looked like a normal variant could have been compared with one he’d had done a few years ago as part of a routine health check.
The way I do tests, treat patients and predict their outcomes is stuck in the 1990s when I started out at medical school
Then AI could have interpreted the subtle changes compared with his old ECG for what they were – the first signs of a lack of blood flow to the heart.
But my interpretation of his ECG was based on how it looked compared to other people’s (in the general population).
Precision medicine also means that if I needed to give a treatment, I would have tailored his dose according to how his body breaks down drugs based on his particular genes and gene variations.
This is currently hypothetical, but it’s far from fanciful. As that new research I mentioned shows, it’s just around the corner.
Published last month in one of the most respected journals, this groundbreaking study by researchers from Massachusetts General Hospital and Harvard Medical School looked at the full blood count test results from more than 12,000 healthy adults over a 20-year period.
What they found was nothing short of remarkable: each person’s blood count remained astonishingly stable over time, fluctuating within a narrow, personal range – what the researchers called individual ‘haematological setpoints’.
They also found that if your blood result changed from your baseline, even if it stayed within what is traditionally thought of as normal, it was a sign of potential disease.
For example, a white blood cell count that was normal but had increased from the patient’s baseline was linked to a higher chance of them dying in the following year.
And the study showed not all ‘normal’ results are reassuring. For example, if the amount of haemoglobin in your red blood cells was marginally above or below average, it was associated with a greater risk of a heart attack or stroke within ten years.
The clinical implications of this study are huge. By using personal setpoints instead of population-wide averages, we can develop more accurate tests for conditions such as diabetes and kidney disease, as well as screening tests.
And ditching the ‘one-size-fits-all’ arbitrary cut-offs for tests and treatments – with doctors instead tracking your personal data over time – has the potential to transform healthcare, allowing doctors to spot disease at its earliest, most treatable stage.
It could also reduce unnecessary treatments, sparing anxiety and interventions for conditions people don’t actually have.
So what can you do for your own health until personalised and precision medicine is the norm?
Firstly, keep track of your blood results and look for trends rather than just if it’s normal or not.
And if your doctor tells you something is ‘slightly low’ or ‘slightly high’, ask for a follow-up test in a few months to see if
it’s a one-off fluctuation or part of a trend. Similarly, if you get a blood test that is classed as abnormal because it is outside the range of 95 per cent of the population, don’t panic – it may be entirely normal for you.
The old-school method of relying on population averages will soon look as outdated as treating infections with leeches.
In the meantime, the best thing you can do is to make sure the blood drawn out of you is used in the best possible way.
