Why is this research needed?
Stroke survivors are at an increased risk of having a second stroke. Allopurinol has shown promise as a drug to reduce stroke risk. But studies in lots of people, over a long period of time are needed to show if allopurinol should be taken to reduce the risk of stroke.
Allopurinol is a type of drug called a ‘xanthine oxidase inhibitor’. Allopurinol is used to prevent gout, a condition where salt crystals build up within a joint, causing pain and swelling. It has been shown to reduce a number of cardiovascular risk factors which can lead to stroke. These risk factors are also indicators of scars building upon the brain, called white matter hyper-intensities (WHM). Such WHM appear around the site of a stroke in about 90% of all strokes where blood clots block blood flow to the brain (ischaemic stroke). Critically, WHM are predictive of future stroke, dementia, and cognitive decline.
What are the researchers hoping to do?
In the current study, 464 stroke survivors will take part for two years. Over this time, half of them will receive 300mg of allopurinol twice daily, and the other half will receive an equivalent ‘dummy’ drug.
At the beginning and end of the study, all participants will have a brain scan to compare changes in levels of WHM brain scarring between the allopurinol and the dummy-drug groups. Eligible participants will also form sub-groups to additionally test for heart muscle thickness and blood pressure – both stroke risk factors.
What difference can this research make?
If the study finds that allopurinol has a beneficial effect on stroke survivors, this could justify a larger, worldwide study to confirm the findings and allow the drug to be recommended for stroke survivors to reduce their risk of having another stroke.