"I hope that screening for Alzheimer's will be available on the high street within five years."

"I hope that screening for Alzheimer's will be available on the high street within five years." So says Professor Francesca Coredeiro,  from University College London Institute of Ophthalmology in this BBC news story about a new technology that seems to work in mice and is shortly to be tested in humans for the first time.

High street? Screening? Alzheimer's? ............. Seriously?

That's quite a statement from the Professor. She's talking about a test 'at the opticians'. All the the complexities of screening and Alzheimer's ignored, in order to sound bite the story into health news. There's much further to go than a quick hop, skip and scurry from this mouse based science story. You won't find me ahead of you in the queue just yet. 

A high street optician is not the right place for such a test. And until the test is 'proven' to improve things for people, by opening up a range of options that would change the course of the disease - it is not immediately clear to me what these would be - it is not going to be available on the NHS any time in the next decade. A population screening test will take decades longer. 

The test may only 'work' by labelling more people, more promptly as having Alzheimer's. I'm not sure that counts as progress. It might be, marginally, if they have symptoms and are having trouble accessing social care or respite services. However, the point seems to be that the test would work in people who are ostensibly symptom free i.e. well. What possible advantage does an early test for Alzheimer's give you, if you are currently well?

The only reason opticians enter the equation in a screening role is because it is an eye test. That is a good argument for moving these proposed Alzheimer's screening eye tests (if they ever come into clinical use - a big 'if', as the results, so far, are on mice) into acute or primary care services, with a multidisciplinary team built in. There's not enough back up of that kind in a high street optician's. 

How can an optician go through the informed consent process and counselling on the risks and benefits of the test, when they have have no experience of caring for people with Alzheimer's unless, perhaps, they have needed glasses? That sounds facetious but it is a real concern.

I doubt the Professor had in mind that the optician would also deliver the results but, even so, responsibility for counselling on whether or not to take a test is not appropriate for opticians. A conversation about the ins and outs of what being diagnosed with Alzheimer's might imply is best held with your GP. He or she has an entire working life based on answering all the difficult questions you or your family might have about health and medicine. A GP would also be well placed to uncover apparently unconnected underlying fears or anxiety that might manifest in someone with no symptoms pursuing a test for Alzheimer's. 

You could separate the counselling and the test so the GP does one and the optician does the other, but that is still unneccessaritly complicating. The professor may have merely trying to illustate the likely convenience of the possible test rather than seriously promoting the role of opticians as cut price GPs, but maybe not. She might be like everyone else, who think all effects of screening are positive. They are not. 

As this is trailed as a test that identifies Alzheimer's before it produces symptoms, it could shorten working lives, make you uninsurable or blight a previously happy retirement with shattering news. So you have to think very carefully whether or not such a test would be right for you. Or hope that parallel drug developments that stop deterioration at the pre-symtomatic stage come on stream before the test does. 

It is a qualified 'yes' to the test, on two counts - 1) if it ever gets out of the mouse model and 2) if it does actually improve the lives of people with Alzheimer's. However, any evidence base for a screening programme won't emerge for another couple of decades at least.  And don't hold your breath for screening on the high street within five years. That's puff, fluff and PR.