Weighing up the potential benefits and harms of comprehensive full body health checks

Most people are familiar with the concept of undergoing general health checks. This might mean that your doctor talks to you about your medical history and lifestyle including diet, physical activity, alcohol intake and smoking history. This is part of providing holistic care to identify and address risk factors to prevent disease. Health checks are also performed as part of national screening programs, such as the national cervical cancer screening program, which aim to detect and treat disease early.

However, a less familiar form is the general or ‘full body’ health check that not only involves a comprehensive clinical assessment, but also includes performing a whole battery of laboratory, genetic and imaging tests in a person who does not feel ill and has not sought care. General health checks are a common element of health care in some countries and purport to be able to detect disease early, prevent disease from developing, and provide reassurance. In Australia this type of comprehensive full body health check-up may be offered to company executives or directly advertised to the general public, targeting the ‘worried well’.

But do these full body check-ups truly deliver on their stated aims and are there any potential downsides?

In the article below, Dr Romi Haas and Professor Rachelle Buchbinder describe how testing asymptomatic people to ‘screen’ for a range of diseases as part of these types of general health checks can be dangerous. They outline what people need to know before consenting to such checks and suggest improved regulation of public advertising could help in ensuring the judicious and informed use of screening.

This article is published as part of the TOO MUCH of a Good Thing series, which is investigating how to reduce overdiagnosis and overtreatment in Australia and globally, and is published as a collaboration between Wiser Healthcare and Croakey.

To follow the series, bookmark this link, and follow #WiserHealthcare on Twitter.

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Romi Haas and Rachelle Buchbinder write:

One-page advertorials are appearing in Australian and regional newspapers for something called “HealthScreen”, with the headline “The future of medicine is here now”. HealthScreen is a direct-to-consumer service that conducts a variety of assessments that search or ‘screen’ for signs of disease in people who are not displaying any signs or symptoms (asymptomatic).

These general health checks offered by HealthScreen cost AU$2,000 and include Magnetic Resonance Imaging (MRI) scans for 20 of the most common cancers, coronary heart disease and stroke risk assessments, genetic screening, laboratory tests and sleep health evaluation. The $2,000 cost is not covered by Medicare or private health insurance. It is also only an initial cost: it does not include the associated cost of the inevitable additional tests as well as treatments that will follow for many people.

A quick Google search has revealed that HealthScreen is not alone in offering comprehensive general health checks. In Melbourne alone, similar services are also offered by Epworth HealthCheck, Life First, Men’s Health Melbourne and National Institute of Integrative Medicine.

HealthScreen’s promotions say they aim to identify medical conditions that “are likely to reduce life expectancy before the onset of symptoms or any indication of a problem”. They promise their clients will know they “are doing everything possible to take control of your health and longevity”. Framed this way, parting with $2,000 to future-proof your life might sound quite appealing to those who can afford the cost. But can it truly be this easy or is it too good to be true?

This type of screening is highly likely to lead to further tests. This is because screening tests like these are not designed to be diagnostic, but rather to identify people who are at higher risk of developing a disease so they can have further diagnostic testing. Positive screening tests require confirmatory tests to definitively rule in or rule out disease.

In fact, in December 2019, HealthScreen reported that “so far the doctors have found hidden problems in every patient”.

So what is the evidence that finding ‘hidden problems’ is beneficial in future-proofing your life?

Potential for more harm than good

This is not simply a question of cost. Before consenting to undergo such general health checks, it is important to be fully informed about both the potential benefits and the potential harms of undergoing such a comprehensive check-up.

The best available evidence evaluating the benefits and harms of these types of health checks indicates they are unlikely to be beneficial. A recent update of a Cochrane review included 17 trials, 15 of which reported outcome data from more than 250,000 people in total. As well as a comprehensive clinical assessment, the trials assessed various combinations of blood, urine and lung function tests, electrocardiograms, cancer screening, and vision and hearing assessments.

It found high-certainty evidence that general health checks have little or no effect on either overall mortality or death from cancer, and moderate-certainty evidence that they probably have little or no effect on fatal or non-fatal heart attacks or strokes. General health checks offered by various organisations are therefore not evidence-based; they have not been shown to increase life expectancy.

As well as being unlikely to be beneficial, full body general health checks in asymptomatic people can potentially be harmful. The main harms are overdiagnosis, detrimental psychological effects, negative effects on health behaviours (for example, failure to quit smoking due to reassurance of good health), complications related to follow-up tests, and unnecessary treatments.

No screening test is one hundred percent accurate. There is always a trade-off between sensitivity (correctly identifying when you do have a problem) and specificity (correctly identifying when you don’t have a problem). Tests with high sensitivity but low specificity have a higher chance of false positive results (saying you have the disease when you don’t).

A positive screening test always requires further confirmatory or diagnostic tests. A false positive result cannot help you because you do not have the disease but it can harm you from unfounded worry and stress. Tests with high specificity but low sensitivity have a higher chance of false negative results (missing people who have the disease). False negative results can provide false reassurance, delay detection of disease, lead to legal action and reduce public confidence in screening programs.

Overdiagnosis is another harm that should be considered when weighing up the potential harms and benefits of full body general health checks. This occurs when a test leads to a diagnosis that would never have caused any symptoms or problems within a person’s lifetime.

In cancer testing, for example, this can happen because a tumour may grow so slowly that a person dies of something else before it starts to cause symptoms, a tumour may not grow at all or a tumour may even disappear without treatment. In each of these cases the diagnosis has no direct benefit since no treatment is needed.

However, the diagnosis can cause harm through unnecessary psychological distress, adverse effects associated with unnecessary further testing (overtesting) and unnecessary treatment including surgery (overtreatment), and unnecessary medical costs. A recent study has estimated that in Australia nearly one in five cancers diagnosed in men and one in four cancers diagnosed in women are overdiagnosed cancers.

HealthScreen uses “state-of-the-art” medical imaging such as MRI and CT scans to look for ‘hidden problems’ in people. While these types of tests were not evaluated in the trials included in the Cochrane review, paradoxically, the use of such sensitive testing technology has been identified as a major source of overdiagnosis.

Because they are so sensitive, they can detect minute tissue changes that may not ever cause any symptoms. For example, there is evidence to suggest that very small thyroid papillary tumours are being overdiagnosed and overtreated in people who have no symptoms but have been tested for some other reason with a CT scan, MRI scan or ultrasound.

These scans also detect degenerative findings that commonly occur with age. For example, degenerative changes in the low back, knee and shoulder are seen with ageing in people with and without symptoms, and are mostly benign. If full body checks find these changes in people without symptoms, it can lead to unwarranted diagnoses, cause worry and lead to unnecessary treatment.

There is also concern that screening the genes of healthy people may cause a whole new wave of unnecessary diagnoses. This is because genetic testing is often unable to determine if a person will show symptoms or whether the condition will progress over time.

One example of harm that may arise from full body general health checks is treating high levels of uric acid detected in the blood in people without symptoms. While allopurinol is the mainstay of treatment for gout (a form of arthritis causing painful joints), prescribing this treatment solely on the basis of a high uric acid is not recommended.

In a large population-based study, people taking allopurinol were 10 times more likely to end up in hospital because of a severe skin reaction than in those who did not take allopurinol. And two out of every 10,000 of these people died from the reaction.

Regulating public advertising

It seems HealthScreen is not alone in advertising the benefits of their services without adequate consideration of the potential harms.

A recent project by Professor Ken Harvey at the Monash University School of Public Health and Preventive Medicine known as the “whack-a-mole” project has resulted in a considerable number of individual complaints against claims made about therapeutic goods and services being upheld. This means that the manufacturer or service provider had made claims for a product or service which were not supported by evidence.

Greater regulation of direct-to-the-public advertising for whole body health checks in Australia may be needed. At the very least, companies such as HealthScreen should ensure their advertising includes outline of the potential harms as well as the potential benefits of participating in their services.

Healthscreen’s Medical Director, Dr David Badov, was invited to address the concerns laid out in this article. His response can be found here.