Researchers have identified a potential cause for lacunar strokes, a type of stroke affecting around 35,000 people in the UK each year. The discovery could explain why current treatments often fail and pave the way for new therapies.
Lacunar strokes result from damage to tiny blood vessels deep within the brain, leading to severe issues with thinking, memory, movement, and ultimately dementia. Unlike ischaemic strokes, which are caused by blocked arteries, a study by the University of Edinburgh and the UK Dementia Research Institute suggests that lacunar strokes may stem from the widening of arteries.
The study, involving 229 individuals with lacunar or mild non-lacunar strokes, tracked brain changes and cognitive function over a year. Analysis found no link between lacunar strokes and arterial narrowing. Instead, patients with widened arteries were four times more likely to suffer this type of stroke, a pivotal finding for future treatment development.
This could explain why standard treatments, such as anti-platelet drugs that prevent blood clots, are ineffective for lacunar strokes. Widened arteries were also linked to a higher risk of silent strokes, which occur without obvious symptoms. More than one in four patients had silent strokes during the study despite receiving preventive treatment.
Professor Joanna Wardlaw of the University of Edinburgh said: “This study provides strong evidence that lacunar stroke is not caused by fatty blockage of larger arteries, but by disease of the small vessels within the brain itself. Recognising this distinction is crucial, because it explains why conventional treatments like anti-platelet drugs are not as effective.”
The findings, published in the journal Circulation, are being used in trials such as the LACunar Intervention Trial 3 (LACI-3), which is testing existing drugs against the condition. Maeva May of the Stroke Association called for more research funding, noting that less than 1% of UK research spending goes to stroke, and urged that such studies become a national priority.
