A new study by the UK’s University of Exeter Medical School has concluded that people who have had a stroke have a higher risk of developing dementia.
The researchers analysed data from a total of 3.2 million people globally.
Even when other dementia risk factors such as blood pressure, diabetes and cardiovascular disease were considered, the link between the conditions remained.
The team based their study on previous research that established the link. However, the original research failed to identify the degree to which stroke increases dementia risk.
Researchers examined 36 prior studies for the latest study, with data coming from 1.9 million people who have had a stroke.
The researchers further analysed additional 1.3 million people across 12 different studies. This focussed on whether subjects had had a recent stroke over the study duration.
It was observed that dementia risk more than doubled if participants had a stroke previously.
University of Exeter Medical School researcher Ilianna Lourida said: “We found that a history of stroke increases dementia risk by around 70%, and recent strokes more than doubled the risk. Given how common both stroke and dementia are, this strong link is an important finding.”
Lourida added that improvements in prevention and care of stroke may help in dementia prevention.
The team noted that additional research is needed to assess the impact of factors such as ethnicity and education on the risk of dementia after a stroke.
As majority of people who have a stroke do not develop dementia, more research is required to study how post-stroke care and lifestyle further affect dementia risk.
University of Exeter Medical School researcher David Llewellyn said: “Around a third of dementia cases are thought to be potentially preventable, though this estimate does not take into account the risk associated with stroke.
“Our findings indicate that this figure could be even higher, and reinforce the importance of protecting the blood supply to the brain when attempting to reduce the global burden of dementia.”