Science
Hope for first treatment for strokes linked to dementia
Two cheap and common drugs could be re-purposed as the first specific treatment for people who experience a type of stroke linked to nearly half of all dementias, according to the results of a clinical trial we have funded presented today at the American Heart Association International Stroke Conference.
Lacunar strokes affect at least 25,000 people in the UK each year. They’re thought to be caused by cerebral small vessel disease (cSVD), where small blood vessels deep within the brain become damaged and stop working properly. Lacunar strokes can have distressing effects as people may develop problems with their thinking and memory, movement, and even dementia. There are currently no effective treatments.
Now, a clinical trial has shown that isosorbide mononitrate and cilostazol, which are already used to treat other heart and circulatory diseases, can safely and effectively improve the debilitating outcomes people experience after lacunar stroke, particularly when they’re used in combination.
Possible treatment within five years
The two drugs could be available as a treatment for lacunar strokes within five years, if the results are confirmed in further trials, according to the trailblazing trial team at the Universities of Edinburgh and Nottingham, led by Professors Joanna Wardlaw and Philip Bath, and the UK Dementia Research Institute.
The trial involved 363 people who had experienced a lacunar stroke. As well as their standard stroke prevention treatment, participants took either isosorbide mononitrate or cilostazol individually, both drugs together, or neither, for one year.
The researchers investigated cilostazol and isosorbide mononitrate as they are thought to improve the function of the inner lining of blood vessels (the endothelium). Problems with the endothelium are thought to play a role in cSVD.
Fewer problems with thinking and memory
After one year, participants that took both drugs were nearly 20 per cent less likely to have problems with their thinking and memory compared to the group that did not take either drug. They were also more independent and reported a better quality of life.
Those who took isosorbide mononitrate were less likely to have had further strokes at one year than those who did not take the drug.
Individually isosorbide mononitrate also improved thinking and memory skills, and quality of life, while cilostazol improved independence and mood. But these effects were strengthened when the two drugs were taken together.
The team is now planning to test these drugs in a larger four-year clinical trial, which they hope to start by the end of 2023. They are also looking to test whether the drugs are effective in different conditions linked to cSVD, such as vascular cognitive impairment and dementia.
'A long-awaited positive step'
Professor Joanna Wardlaw, Chair of Applied Neuroimaging at the University of Edinburgh and Foundation Chair at the UK Dementia Research Institute, said: “Up until now, lacunar strokes have been treated just like other types of stroke, but lacunar stroke is clearly different. Now we understand more about what is triggering these strokes to attack the brain, we’ve been able to focus our efforts on treatments that can put a halt to this damage.”
“We need to confirm these results in larger trials before either drug can be recommended as a treatment. However, as these drugs are already widely available for other circulatory disorders, and inexpensive, it shouldn’t take too long to move our findings from research into everyday clinical practice.”
Professor Sir Nilesh Samani, our Medical Director, said: “These promising findings provide a long-awaited positive step towards the first treatments becoming available for lacunar strokes, offering much needed hope for thousands of people.
“Lacunar strokes are not the only way that cerebral small vessel disease can affect someone. These findings also open new avenues of research into other conditions related to small vessel disease, such as vascular dementia.”
This research was also supported by the UK Dementia Research Institute.