Is it worth getting an annual medical check-up?
Evidence suggests they are ineffective in some cases and can lead to unnecessary testing. Paul Biegler reports.
A perspective piece in the journal JAMA has questioned the value of the time-honoured annual check-up at the family doctor, citing a recent study that found it is of doubtful benefit and may lead to unnecessary tests and treatment.
The author, JAMA senior writer Rita Rubin, refers to a Cochrane Review, published in January, which found “high certainty” evidence that giving healthy adults tests such as blood pressure, cholesterol, ECG and screens for various cancers does not improve outcomes.
The Cochrane Review looked at 17 randomised trials covering more than a quarter of a million adults, concluding that “health checks have little or no effect on the risk of death from any cause... or on the risk of death from cancer”. The review also found health checks “probably have little or no effect on the risk of death from cardiovascular causes”.
The results seem to fly in the face of an axiom in medical care; the idea that prevention is better than cure. So, what is going on?
The Cochrane Review authors suggest a range of possible reasons for their findings.
People in studies who accept invitations for check-ups, they write, tend to be from higher socioeconomic groups, which already puts them in a lower risk category for cardiovascular disease. And doctors are likely to initiate screening on higher risk patients anyway, when they come in to the clinic with other problems.
But another explanation points to limitations in the Cochrane Review itself.
It is an update from a 2012 review and is heavily weighted to older studies, some from the 1960s and 1970s. That’s an era well before the advent of statin drugs for high cholesterol and ACE inhibitors for high blood pressure, meaning the doctor’s arsenal was relatively depleted.
The review does, however, include recent results from the Inter99 study, published in 2014.
Beginning in 1999, Inter99 randomised 60,000 adults from Copenhagen, Denmark, to be screened for cardiovascular risk over five years, including questions about symptoms and family history, as well as tests of blood pressure, cholesterol, ECG and blood sugar.
High risk people were counselled about diet, exercise and stopping smoking. The control group was not invited to be screened.
When the groups were followed-up after 10 years, screening and counselling had precisely zero effect on heart disease, stroke or overall mortality.
Lasse Krogsbøll, a Copenhagen-based surgeon and co-author on the Cochrane Review, told JAMA that Inter99 and other recent inclusions to the updated review might not show any benefit of check-ups because they were done in countries where people already have good access to primary care.
“One of the most important things to note is everybody in the control groups had access to a general practitioner,” says Krogsbøll. “This is not a matter of health checks vs no primary care.”
The issue is pressing, not least because untangling the question of whether check-ups actually do anything has plenty of money riding on it.
Choosing Wisely, an initiative of the American Board of Internal Medicine that aims to stamp out ineffective “low value” healthcare, estimates $300 million is spent each year on unnecessary tests ordered in annual check-ups. It says, bluntly, that “annual physicals usually don’t make you healthier”.
In Australia, which spends over $2 billion annually on preventive health care, Choosing Wisely recommends against a range of low value tests; some of those aim at prevention, such as doing ECGs on low risk people with no symptoms.
Australian GPs can claim a Medicare fee for doing a health check on people aged 45 to 49 who are at risk of developing a chronic disease, such as diabetes, asthma, cancer or a mental health condition.
But modelling published in November 2018, led by Si Si at Curtin University in Perth, Western Australia, found individual health impacts of the check to be “small”, concluding that the “health check is highly unlikely to be cost-effective”.
Perhaps one of the most troubling aspects of pre-emptive testing, however, comes from a quirk of statistics.
When you screen a group of people in whom the prevalence of disease is low, such as healthy folk with no symptoms, the number of people who return a positive test that actually have the disease drops too. That is, you get lots of “false positives”.
But you can only know those positive tests are false once you’ve gone through the gamut of follow-up tests that prove the disease isn’t there. And those tests can be invasive and sometimes harmful.
That issue was highlighted in a 2018 analysis of the Prostate, Lung, Colorectal, and Ovarian (PLCO) cancer screening trial. It ran from 1993 to 2001 and, with more than 150,000 participants, is one of the largest such studies ever undertaken.
Conducted by researchers from the US National Cancer Institute and the National Institutes of Health, the 2018 analysis found that, of all the screening tests for those four types of cancers that came back positive, a hefty 96%were false positives.
That result meant 3314 men had prostate biopsies, 16,379 people had endoscopies or colonoscopies and 1072 women had ovarian surgeries that did not lead to a cancer diagnosis. And each of those procedures comes with its own set of risks.
It must be noted, however, that in Australia the professional body for doctors, the Australian Medial Association (AMA), backs regular check-ups.
An AMA spokesperson said, “High quality health checks incorporate more than screening for cancer or cardiovascular disease, including mental health, sexual health, and family planning.
“Health checks are an important part of preventive care and the AMA encourages Australians to see their GP regularly.”
Amid the conflicting views, what seems clear is that a good relationship with your GP, and a prudent approach to getting tested, could well be the best medicine.