It is taken as read that check ups and screening are good for us. The logic is almost intuitive. Finding disease early is better than finding it late as treatment can be more effective. Also not everything has symptoms so testing and checking may uncover problems before they manifest and cause illness or even death.
Indeed people are virtually pressured to go along for a check up or the be screened so their “life can be saved”. Those who do not are made to feel guilty. Groups like breast screen will send out reminder letters for those who abrogate their “duty”.
Doctors too are under pressure to do screening so that their quotas match government targets. An Australian survey showed the number of general checks done by GP’s increased by 1.4 million per year in the nine years from 2002/03. In the UK the quota system is worse. Those who have the “temerity” to be healthy are chided for not going to the doctor.
So what could possibly be wrong?
Quite a bit as it turns out!
A Cochrane Collaboration review published in The British Medical Journal of 16 trials of health checks in middle aged people involving 182,000 people concluded “general health checks did not reduce mortality or morbidity, neither overall, nor for cardiovascular or cancer causes, although they increased the number of new diagnoses. Important harmful outcomes were often not studied or reported”.
This pertains to healthy people without any symptoms. Diagnostic testing where there are symptoms is completely different.
Simplified; check ups do not reduce illness or affect life expectancy! This was both for all cause mortality (death from anything) and specifically for cancer and cardiovascular disease. These are the two areas where screening is most recommended.
It gets worse. The fact that there were new diagnoses but no change in outcome means people have been tested and likely treated without them getting any benefit. The prime examples of this would be diagnoses of hypertension (high blood pressure) and hypercholesterolemia (raised cholesterol). Reviews have shown that treatment of mild hypertension does not affect mortality or rates of heart disease or strokes. Treating isolated raised cholesterol has also not been shown to affect mortality.
So people are “diagnosed” which makes both doctor and patient feel that something has been achieved. In most instances people will be prescribed medications. This will also make both doctor and patient feel like they are doing something beneficial.
But whilst we may change numbers on a blood pressure cuff or blood test we are not changing heath outcomes. Worse still some of the people we treat may have side effects and suffer harm from treatments. In the elderly there is a 43% increased rate of hip fracture in the first 45 days. Statin medications to lower cholesterol can cause fatigue and muscle soreness as well as impact the liver.
Side effects can be justified if the benefits of treatment outweigh the risks. If there is no benefit even small risks cannot be justified.
With regards cancer-screening logic would suggest that finding cancers early leads to better outcomes. I have written about the problems of prostate screening previously. PSA testing does not reduce mortality and indeed for every three lives “saved” one will be lost needlessly and some 130 will suffer considerable harm such as incontinence. This does not even include harms from needless worry or unnecessary biopsies.
The scared cow of screening is mammography.
Previous reviews have shown no difference in breast cancer mortality in different countries where mammography was introduced at different times and that there is an up to 40% rate of over diagnosis. A new review published in the New England Journal Of Medicine showed that over three decades some 1.3 million American women had been over diagnosed with breast cancer. This means they had tests and treatments, which have not improved or extended their lives.
I strongly urge you to watch this video by Dr H. Gilbert Welch explaining how the considerable increase in early stage breast cancer found has NOT lead to a reduction in late stage cancer. In other words the vast majority of these early stage ones found on screening would not have manifested! If screening was “working” there should have been a significant drop in late stage cancers. After all if they are found early they do not get found late-by definition!
Success has many authors and there has been an improvement in breast cancer survival over the last 30 years. This has been due to better treatment not screening. Naturally if you find lots of tumors that would not have killed people, survival rates go up even further.
We are constantly told how it saves lives. The reality is that as a screening test it does not. As a diagnostic test (when there is a lump) it is useful. Women have been told that a mammogram is the most important thing they can do for their health – it is not!
Some will say that they or someone they know is alive today because of a mammogram. If a non-fatal cancer were found it is not the mammogram, which has saved the day – you would have lived anyway and did not need surgery or other treatment.
The marketers of screening have done a great job convincing doctors and consumers. A New Zealand study showed people significantly over estimated the benefits of checks and screening by a factor of 10 to 100 fold. “ Our findings suggest that patients overestimate the benefit of widely used preventative medications and screening programs,” the authors said.
They were unclear the cause of the optimism. I reckon its because the marketers of screening have done a great job convincing doctors and consumers of the “benefits” whilst ignoring or downplaying the risks.
The facts tell a different story to the hype. Unfortunately you may not even recognize that you have not been helped. You may believe that the diagnosis and the tablets have helped you or the surgery has saved your life.
An American farming adage says “You don’t fatten the hog by putting it on the scales”. Testing for disease is not the same as being healthy. This involves looking after yourself on a daily basis. It includes eating sensibly, exercising, managing stress, and getting enough sleep – the pillars of health. Plus if needed getting input from a doctor or other health professional.
Many patients say to me that screening means being better safe than sorry.
In reality screening is not always safe and you may be very sorry.