7 April 2021

Stroke risk higher after traumatic brain injury

Clinical Neurology

The risk was significant for several years after both mild and severe brain injuries, researchers say.

In adults, traumatic brain injury – regardless of severity – almost doubles the risk of stroke in the next five years, UK research shows.

The findings of a UK meta-analysis suggest patients who have had a traumatic brain injury need more education on recognising and urgently responding to stroke symptoms to improve health outcomes, the authors said.

Researchers studied the rates of ischaemic or haemorrhagic stroke risk following a TBI of any severity across 18 studies including more than 2.6 million people from four countries (the US, Taiwan, Croatia and Denmark).

They found that the risk of stoke was 86% higher among individuals who had a traumatic brain injury, and this held true regardless of stroke type, injury severity and injury subtype.

This was a particularly important finding given 70%–90% of injuries were considered ‘mild’, or concussions, the authors said.

The risk of stroke was highest in the first four months after the brain injury but the increased risk remained significant for five years.

The researchers suggested their findings had practical implications for clinical practice.

“It may be beneficial to inform TBI patients of their potential increased stroke risk and educate them to recognise and respond urgently to stroke symptoms,” they wrote in International Journal of Stroke.

“Primary stroke prevention is important to reduce stroke incidence and subsequent stroke-related death and disability; therefore, clinicians should review patients’ stroke risk post-TBI and consider administering stroke prevention medication and lifestyle advice.”

Some evidence suggested that stroke was less common in patients who took stroke prevention drugs such as vitamin K antagonists and statins, although these drugs were often ceased following a traumatic brain injury.

“Other research has found older age and risk of falls are common barriers to clinicians’ prescribing stroke prevention drugs. This is particularly relevant given the shift in TBI epidemiology in high income countries to falls in the elderly,” they said.

Stroke Foundation’s clinical council chair, Professor Bruce Campbell, called for caution in interpreting the study’s finding.

One has to balance the potential risk of a future ischaemic episode with the increased risk of haemorrhage associated with trauma.

“The study may serve as a reminder to restart stroke prevention medications for appropriate patients once the initial risk period for bleeding after the trauma has passed,” said Professor Campbell, who is also a consultant neurologist at the Royal Melbourne Hospital.

International Journal of Stroke 2021, April 4