Have a brain injury? You may be at higher risk for stroke

People who have a traumatic brain injury (TBI) may be more likely to have a future stroke, according to research that appears in the June 26, 2013, online issue of Neurology®, the medical journal of the American Academy of Neurology.

"Both stroke and traumatic brain injury are common, costly, and leading causes of severe disability in adults, and approximately 20 percent of strokes occur in adults under age 65," said study author James F. Burke, MD, MS, of the University of Michigan and the Ann Arbor VA Healthcare System and a member of the American Academy of Neurology. "A large proportion of stroke risk is unexplained, especially in the young, so if we can identify new risk factors, we have the potential to prevent more strokes and improve outcomes."

For the study, researchers looked at the records of adults who went to the emergency department or were admitted to a hospital for TBI or other trauma with no brain injury in the state of California during a five-year period.

A total of 435,630 people with traumatic brain injury were studied, along with 736,723 people with trauma with no brain injury. Over an average of 28 months following the injury, 11,229 people, or 1 percent, had an ischemic stroke. A total of 1.1 percent of those with TBI suffered a stroke, compared to 0.9 percent of those with trauma with no brain injury. With an ischemic stroke, blood flow to part of the brain is blocked. Eighty percent of strokes are ischemic.

After adjusting for factors that can affect stroke risk, such as age, high blood pressure and high cholesterol, as well as other disorders such as heart disease and the severity of the trauma, the researchers found that people with traumatic brain injury were 30 percent more likely to develop a stroke than those with trauma with no brain injury.

"While the stroke risk of one person with TBI is small, the overall link between TBI and stroke was substantial - as large as the link between the strongest stroke risk factor, high blood pressure, and stroke," Burke said. "If further research establishes TBI as a new risk factor for stroke, that would stimulate research to help us understand what causes stroke after TBI and help us learn how to prevent these strokes."

A Stroke is Not a TBI

A stroke is not a form of traumatic brain injury (TBI).

The word "traumatic" in the definition of TBI relates to the cause of the brain injury, not the fact that people feel traumatized from their brain injury. And of course, people with strokes or brain illnesses feel just as traumatized as people with TBI. But TBI's result from external forces such as being hit by a car or bullet or falling off of a ladder or roof top.

Strokes, tumors, and brain illnesses are not TBI's. The term "tbi survivor" has become so generalized, so popularized by the tbi community, that many people with a stroke or tumor think they are also tbi survivors. Not so. Instead, one is a stroke survivor, or a tumor survivor, or an anoxic brain injury survivor, or a meningitis survivor. Individuals with these other forms of acquired brain injury are not tbi survivors. However, they may lay claim to being abi survivors. Everyone with an acquired brain injury (and that would include from illness, stroke, toxin, trauma, or tumor) may lay claim to being an ABI survivor.