30-40 per cent of breast cancers detected on screening mammography are over-diagnosed, prompting women to have surgery.
One of the great misnomers of our time is the term “health system”.
What we have is in fact a disease system. Virtually all the money spent on “health” is actually spent on disease.
In all the arguments about budgets each year, two questions never get asked. The first is how much of the money we spend on “health” actually benefits people. The second is how much harm is done in the name of “health.”
Scientists say we regularly test blood pressure, but does that help us diagnose disease?
Over the last 30 years there have been three major trends, which have been accepted unquestioningly up until very recently. First is the introduction of screening tests where healthy people are tested for the possible presence of early disease. Second is our increasing ability to diagnose and treat “conditions” with no symptoms such as high blood pressure. The third is a relentless lowering of thresholds at which we classify people as having a disease.
All three have led to the over-diagnosis and needless treatment of many healthy people.
The concept of over diagnosis can be difficult to get your head around. It happens when people are “diagnosed” with a condition that would never manifest into a disease or illness during their lifetime. It would never cause any symptoms and would not shorten life expectancy.
Unless it is detected on a screening test, you would never know it was there and the fact that you did not know would not matter. It may seem incredible that such a problem can exist.
But it does exist and the cost in human and economic terms is considerable even though often hidden. Some 30-40% of breast cancers detected on screening mammography are over diagnosed leading women to have surgery and other treatments.
Of course, they are eternally grateful for having their lives saved. Yet what these women don’t know and are not told is that they would have lived anyway.
A Canadian study published in the BMJ followed 89,835 women over a 25-year period. It found no difference in deaths from breast cancer (505 versus 500 in 25 years) in women who did or did not have regular mammograms.
It also showed that one in every five cancers found on screening were not going to be a threat to health and did not need treatment. Some previous reviews have put the over diagnosis rate as high as 40% or four out of every ten.
The situation is similar with prostate cancer. For every 3000 men having a screening PSA (prostate specific antigen) blood test done, three men will live longer. One will die due to complications of treatment he didn’t need. Some 129 will suffer harm from surgery and complications of treatment. Not great odds really.
This has come about because our understanding of cancer has not matched our ability to detect it. Not all cancers grow and develop. The American Cancer Council is looking at reclassification of early stage “harmless” growths using a term other than cancer, as they are not cancers in the way we think about cancer.
In heart health, it has been shown that there is no basis for current blood pressure recommendations. They seem like a good idea but there is no evidence to support them. You would hope that lifelong treatment with medication was based on more than a good idea.
Especially as treatment “targets” have been steadily lowered over the years and side effects are not always insignificant. The elderly, in particular, can faint and fall if their pressure is too low.
And there is the lowering of thresholds for “treating” raised cholesterol with statin medications. Again, major reviews have shown no benefit in people who do not have existing heart disease.
The cost to individuals and the system of tests, medications and other treatments, which do not improve health, is massive. Reducing this would free up plenty of money to be applied where it would actually provide benefit.
Is it that simple? Of course it is not. But unless we actually ask questions about usefulness we will never get answers. Overseas, interest among doctors and others in the health system is growing and this year the second international conference on over diagnosis will be held in the UK.
We have been sold the notion that early detection and treatment is all good. If we fully understand the benefits and risks, we can make an informed decision. When we are told simple tests will save our lives we are being told only a part of the story. In no other industry are unbalanced claims like this allowed.
As a society we need to be more questioning of how money is spent in the “health system.” As individuals we need to be much more questioning about claims of benefits from tests and treatments for problems, which probably won’t affect our health or longevity especially when the tests and treatments can cause us harm.
Dr Joe Kosterich is a GP and a health industry consultant