The cause of a type of stroke that affects about 35,000 people across the UK each year has been uncovered by researchers and may explain why some medications are ineffective as treatment. Lacunar strokes, which account for a quarter of all strokes in the UK, had been linked to the blockage of arteries in the brain by fatty deposits. However, a study published on Wednesday suggests they are not caused by blocked arteries but by the enlargement and widening of arteries in the brain. This would help to explain why aspirin and other blood thinners, commonly used to prevent ischaemic strokes, are not as effective in preventing lacunar stroke. The research by academics at the University of Edinburgh and the UK Dementia Research Institute analysed 229 patients who had experienced either a lacunar or mild non-lacunar stroke. Maeva May, the director of policy for the Stroke Association, said the findings “illustrate the value of research and the potential it has to change the lives of stroke patients”.…