Scientific data can be a real headache for politicians, especially when it has an irritating propensity to directly contradict flagship Government policy.
This is exactly what happened last week, when a Cochrane review published the results of a meta-analysis on the efficacy of Health Check-Ups, which was widely reported by the BBC and others. The review looked at the effects of health screening in over 180 000 patients, and concluded that while those screened were more likely to be diagnosed with high blood pressure or raised cholesterol than those not offered the check-up, there was no difference in mortality, hospital admission or disability between the two groups. The review concludes:
From the evidence we’ve seen, inviting patients to general health checks is unlikely to be beneficial.
The problem for politicians is that this is undermines a key health policy from the Department of Health which involves inviting all people aged 40-73 to a health check to look for the risk of heart disease, stroke, type 2 diabetes and kidney disease. And this includes politicians of all the major parties – the policy was introduced by the Labour Government and has been continued by the Coalition.
What should we make of this? Aren’t we used to contradictory scientific headlines telling us that something is terribly good for us one week and causes cancer the next? Well, how hard we should listen depends on the quality and type of evidence before us. A small observational study is a very different piece of evidence to a large randomised trial, or a systematic review of all the evidence. I have borrowed an illustration from Margaret McCartney’s book The Patient Paradox which illustrates this well. It is a hierarchy of the quality of evidence, with the most reliable being at the top:
Cochrane reviews are not only at the top of this hierarchy as a systematic review, but they are also renowned in medicine as being among the most reliable, unbiased reviews that are conducted. They are important, and we should listen to them. Which is exactly what a Department of Health spokesman did not do in response to this important research. When questioned by the BBC, the response was to say:
By spotting people who are at risk of heart attacks, diabetes, stroke and kidney disease we can help prevent them.
The NHS Health Check programme is based on expert guidance. Everyone having a health check is offered tailored advice and support to manage or reduce their risk of developing serious health conditions.
So the power of a Cochrane review has been dismissed on the basis of expert evidence. When you look at the above hierarchy it is easy to see how ridiculous this is – it is like pretending that a pair of Jacks can beat a Royal Flush, it just does not work.
So where does this leave us? Well for the Government the situation is clear: Inviting large numbers of healthy people for routine health check-ups has no discernible benefit and the Department of Health programme should be reviewed. The main reason for this is that since it is of no discernible benefit, it is poor use of NHS funds. The checks themselves still need to be better evaluated, but they are not unreasonable – if you are going to have a check-up then to look at the 4 disease areas in question once every 5 years is probably the thing to do.
The organisations that really need to take note of this study (but they are unlikely to do so as they make too much money from health screening) are the private health providers like BUPA, which offer annual health checks that are far more wide-ranging than the NHS scheme – including many tests which are of zero value (such as measuring urate, the waste product implicated in gout which is uninterpretable in a person who does not suffer from gout) and others which are extremely controversial (such as prostate screening).
For individuals, however, we need an individual approach. When the Government first announced the proposal to invite people for check-ups most GPs felt mildly bemused – hadn’t we been doing this for years? You can always see your GP for a blood pressure or cholesterol check and the only thing that was different in the new policy was the invitations. There may be good reasons to assess your risk of conditions such as heart disease or diabetes, especially if there are particular concerns, such as a strong family history.
We must remember, however, that health check-ups are, by definition, performed on people with no symptoms. When we engage in health screening of any sort we cross a line that transforms us, temporarily, into a patient. We hope that this will be the briefest of forays into this alien world and we will soon return to our lives, unscathed, stamped with a clean bill of health and medical approval. We must always accept, however, that we may just remain a patient for longer than we have envisaged if a problem is picked up. This may have real benefits – such as avoiding a heart attack – but will also incur personal costs, including anxiety, more tests and the possibility of unnecessary treatment.
There is still a place for individual health check-ups, but these need to be tailored to individual risk, and also our personal views on how we like to deal with risk. We need to get away from the concept that every upright citizen “ought to have a health MOT”. We are not cars in need of a certificate of roadworthiness, and health screening is a complex issue: Its benefits are often far smaller than we first realise, and its potential for harm far greater than we like to admit.