The new religion: screening at your parish churchBMJ 2009; 338 doi: http://dx.doi.org/10.1136/bmj.b1940 (Published 20 May 2009) Cite this as: BMJ 2009;338:b1940
- Charles Warlow, emeritus professor of medical neurology, University of Edinburgh
Unusually for me, I went to church. On a Monday. Not to ask forgiveness or to sing a hymn, or to be instructed from the pulpit, but to be screened. After all, if Liverpool Anglican Cathedral can be a venue for corporate dinners, why not a mere church for health (disease) screening?
A vascular screening company had come to town after leafleting many of my neighbours with the message that “four out of five people who suffered a stroke had no apparent warning signs.” I imagine they meant transient ischaemic attacks. In fact four out of five people with a stroke have and are generally known to have one or more vascular risk factors, such as hypertension or atrial fibrillation (not signs maybe, but certainly prognostic signposts). But we mustn’t let awkward facts get in the way of marketing, particularly not to the “worried wealthy” of Edinburgh.
So, without revealing my interest in stroke prevention for the past 30 years, I signed on, paid £152 (€170; $230), and turned up at church, along with other older people who didn’t look as healthy as me. (I thought I had better hide my cycle helmet.) First up was aortic aneurysm screening with ultrasonography by a woman who did not want to be engaged in conversation about what the implications of finding an aneurysm might be. Next it was ankle and arm blood pressure measurements for “troubles with my circulation” (the ankle brachial pressure index (ABPI) for peripheral arterial disease to those in the know), followed by a little non-vascular bonus: osteoporosis screening of my ankle.
Then there was four lead electrocardiography (ECG) to detect “trouble with the two upper chambers of my heart,” but nothing else was proposed, even after questioning by me. (Why not an ECG for ventricular ectopics, maybe, or complete heart block?) Then, finally, carotid ultrasonography to detect “plaque build up.” When I asked them what the implications of this might be, they told me that blood clots could form and cause a stroke. Pressed on the sort of treatment I might be given, they offered a vague notion of blood thinning drugs but nothing about surgery until I asked directly if that might be an option, and indeed it was. “Might that be risky?” I enquired innocently. The answer was that any risks would depend on a full work-up by my GP, with whom I should discuss abnormalities from any of the tests.
All of this was conducted without any privacy (except for the aortic aneurysm screening) on couches very close together, by technicians, in a church. There seemed to be no doctor present, and the team showed no intention or will to engage in a discussion of the implications of false positive or false negative results, the prognostic implications of true abnormalities, or the risks and benefits of any treatments. Of course, there was a disclaimer that normal screening results don’t necessarily mean that no stroke will occur.
This was just screening, nothing more and nothing less, done for profit—with the results to be dumped in my lap within 21 working days and for my GP to sort out the emotional and physical consequences of any abnormality, true or false, even though she didn’t request the tests. So will I bother her with my systolic blood pressure of 140 mm Hg, as the screening company suggested I should? No. Or about the “fairly low to moderate amount of plaque build-up not affecting blood flow velocities” in my right carotid artery? Certainly not. But the less informed might be very worried by this finding. The unsuspecting—and no doubt highly irritated—GP would probably refer on to an NHS neurologist to sort all this out, at the taxpayer’s expense. My aorta and ABPI were normal; what a relief. And unlike my far slicker screening for the Biobank research project, there wasn’t even a cup of tea and a biscuit.
Why is this nonsense tolerated or allowed? Where is the audit of these screening outfits? Where is the partnership with patients, the information sharing that we hear so much about from the Department of Health? Apart from aortic aneurysm screening of men over the age of 65 (which is being rolled out in England anyway), there is no evidence that screening for the other three targets is worthwhile. Opportunistic screening by feeling the pulse, and doing an ECG if it is irregular, identifies at least as many new cases of atrial fibrillation as systematic ECG screening of the sort I paid for; and most of the patients in whom it is detected are at such low risk that the risks and inconvenience of anticoagulation would not be worthwhile. Finding an abnormal ABPI in an asymptomatic person identifies only people at such low risk of vascular events that it is very uncertain whether treatment over and above obvious risk factor control such as quitting smoking would confer any benefit that was worth the risks. As for carotid stenosis screening, although surgical removal of an asymptomatic stenosis reduces the risk of stroke by about a half, the absolute risk without surgery is so low that about 20 operations have to be done to prevent one stroke; in other words, 19 out of 20 operations turn out to be unnecessary.
Inevitably this whole screening circus is liable to whip up anxiety in vulnerable people without discussing or taking the slightest responsibility for the consequences of any abnormalities found. At least—unlike brain magnetic resonance imaging, which is another favourite for the screening privateers—the vascular imaging I had was less likely to throw up incidental findings that might cause anxiety, possibly leading in turn to quite unnecessary treatment. And who pays for the consequences of all this? The NHS, while the circus moves on to the next church with no doubt a rather larger congregation than for Sunday matins.
Cite this as: BMJ 2009;338:b1940
Competing interest: CW was on the data monitoring committee of the Asymptomatic Carotid Stenosis Trial and the Aspirin for Asymptomatic Atherosclerosis Trial.