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By Stephen Beech

Brain bleeds potentially double the , warns new research.

The discovery suggests people who have experienced a brain bleed should be regularly screened for cognitive impairment, say American scientists.

Known medically as intracranial hemorrhages, brain bleeds are caused by a ruptured blood vessel in the brain.

The new study shows that they can double a person’s risk of later in life.

The connection between dementia and ischemic strokes caused by clots that block blood supply to the brain has been known for some time.

But the new study, published in the Stroke, extends previous findings to hemorrhages.

First author , Assistant Professor of Neurology at in New York City, said: “We consistently see an elevated risk of dementia, regardless of the type of bleed.�

Using Medicare insurance claims from 2008 to 2018, Dr. Bruce and his colleagues assessed more than 14,000 people who had various types of intracranial hemorrhages, which cause blood to collect in brain tissue or underneath the skull.

Hemorrhages can occur after head injuries, but the research team focused on those that happened spontaneously.

They observed a two-fold increase in the incidence of first-ever within an average of 5.6 years after an intracranial hemorrhage for those patients, compared with over two million people who did not have a hemorrhage.

The results add to findings from other labs showing that hemorrhages are linked to later cognitive problems. For example, a Danish study discovered that 11.5% of people developed dementia after blood vessels ruptured within their brains, around a 2.5-fold increase compared to the general population.

By comparison, ischemic strokes, typically caused by blood clots, increased the by about 1.7-fold.

Study senior author , Associate Professor of Neurology at Weill Cornell Medicine, says there are a number of reasons why an intracranial hemorrhage increases the risk of dementia.

He explained that hemorrhages may cause dementia directly by triggering the accumulation of a protein called amyloid beta in the brain and its blood vessels, which can disrupt brain function.

Dr. Murthy says hemorrhage and dementia may be indirectly connected because the same factors - such as chronic damage to blood vessels in the brain - increase the risk of both conditions.

He added: “As we see more can follow hemorrhages, we really need to consider the implications.

“For example, assessing the safety of anti-amyloid beta treatments for Alzheimer’s disease in people who have experienced a hemorrhage should become a research priority."

The research team concluded that as new treatments developed for brain bleeds may ultimately lead to patients living longer after an incident, further studies will need to explore how hemorrhages contribute to different types of dementia.