New test to show if vital anti-stroke drugs are working

ABLOOD test that can help prevent stroke victims from having another attack is now being offered on the NHS in a move that experts say will save lives. The test picks up genetic clues that show if patients will not respond to standard treatment – allowing doctors to switch them on to more effective drugs.

Experts say that roughly 25,000 Britons fall into this category, and until now it has been impossible to identify them.

It comes three months after The Mail on Sunday published details of a major report calling for widespread use of the genetic tests, which experts say could prevent tens of thousands of strokes and heart attacks every year.

Dr Alex Doney, a stroke specialist at Ninewells Hospital in Dundee, the first UK NHS unit to offer the test, says: ‘Genetic testing for stroke patients will save lives.

‘For years, we’ve treated stroke patients on a one-size-fits-all basis, meaning people with completely different genetic make-ups receive exactly the same dose of the same drug. Yet we know that for many patients, the current drugs work no better than taking a placebo.’

While the test is being used across 33 NHS hospitals in Scotland, the UK health watchdog, the National Institute for Health and Care Excellence (NICE), is reviewing it for more widespread use.

There are some 1.3million stroke survivors in the UK. The attacks – the most common cause of disability – happen when there are problems with the blood supply to the brain.

There are two types. The most common is ischaemic stroke, where the blood supply is stopped due to a blood clot. These account for about nine in ten strokes.

The other is a haemorrhagic stroke, which happens when there is a bleed on the brain because a weakened blood vessel that supplies the organ has ruptured.

This can happen for a number of reasons, including injury to the head, abnormalities in the blood vessels and bleeding disorders.

Most sufferers must take daily blood-thinning medication to prevent another stroke. The most common, for ischaemic strokes, is clopidogrel, which stops small blood cells called platelets from sticking together – dramatically reducing the risk of clots.

But in about a quarter of patients, clopidogrel does not work because they lack enzymes in the liver needed to process it. Those in this group are missing a gene called CYP219, which carries instructions for making the crucial enzymes.

Now, NHS patients in Tayside are being given a blood test to spot this genetic mutation.

Costing £22 per patient, it is carried out in a matter of minutes shortly after patients arrive at hospital, and clots have been identified. Samples are analysed at a laboratory and results come back within a week. Patients with the genetic mutation are offered alternative blood-thinning medicines, such as dipyridamole, which are equally as effective.

Tailoring drugs to a patient’s genetic profile is known medically as pharmacogenomics, and experts say there is potential to make a huge difference in many areas of medicine.

Dr Doney says: ‘This is the first step towards much broader implementation of this kind of precision medicine. The technology is now so advanced and so cheap to use that it’s now no longer a question of if we should use genetic tests to improve healthcare, but how we should implement it.’

RONALD Chimiak, 68, from Dundee, was one of the first UK patients to have the DNA test, days after suffering a stroke in May. It left the grandfather-of-three without movement in his left arm, and with slurred speech and a drooping left side to his face. He says: ‘I know a few people who have had strokes and they’ve not been the same afterwards. I was worried about going the same way.’

While in hospital, the part-time church volunteer was given the DNA test, which revealed he would not respond to clopidogrel. So he was prescribed another anti-platelet drug called ticagrelor and is now well on his way to recovery.

He says: ‘I can move my arm normally again, my speech has returned and the droop on my face has disappeared. If you looked at me, you’d never have thought I’d had a stroke.’