The word "concussion" often refers to images of professional athletes running in the field, or members of the army in close proximity to an artillery explosion. In fact, most traumatic brain injuries do not occur in athletes or soldiers, but in the elderly.
Adults are more prone to fall and get into a car accident as they age. Although these events are less dramatic than sporting accidents, they can still lead to serious brain trauma. Since 2013, traumatic brain injury in the US has been highest in adults over 75 years of age.
In younger adults, concussion, which is freely defined as trauma that destroys brain cells and disrupts the connection between them, has been found to double the risk of developing dementia in later life. Risks to older adults are considered similar but not studied. However, there may be a decade-old drug that can reduce risk. A study published this week in JAMA Neurology found that statins, a class of drugs used to lower cholesterol, may be slightly protective against dementia in older adults suffering from brain shocks.
Researchers, led by a team at the University of Toronto, tracked nearly 29,000 patients over the age of 66 who were admitted to Ontario hospitals and diagnosed with brain shocks from 2003 to 2013. They also found out which of these patients started taking statins for heart problems within three months of brain shock through the Canadian Universal Health System and the Ontario Drug Program.
The researchers then used these databases to see which of these patients continued to develop any form of dementia after four years. Of the 28,815 patients enrolled in the study who were in the stroke group, about 5,000 patients with dementia, 43 cases per 1,000 people, and more than twice the rate of about 19 cases per 1. 000 people in those who did not have concussion. . However, among those who started using statins, the number of developing dementia decreased to 37 cases per 1,000 people.
Six fewer cases of dementia per 1,000 are small, but suggest that statins can help protect some cognitive functions in the brains that have been closed. The older brain may be able to repair some of the shocks, but other damage may be permanent, says Donald Redelmeier, a professor of medicine at the University of Toronto. Brains can often find a way to bypass forms of permanent damage as they cope with normal aging. However, if deformed proteins accumulate in the brain – as is the case with most forms of dementia – the brain may be less capable of coping.
It is possible that statins help keep the brain's ability to cope with other problems after brain shock, says Redelmeier. It's hard to say why this is so. Because it was a study only for observation, patients were not examined by MRI or CT, and therefore scientists could not tell what was happening in the patient's brain after they were confused and how the statins helped.
Importantly, the Redelmeier team also focused on the rate of dementia in elderly patients who were treated for ankle sprain, and found that they were similar to those who were taking statins and those who were not. This suggests that statins are not universally protected from dementia – although they have no negative consequences for patients.
It is too early to say that anyone who has a concussion should be deployed on statins to prevent dementia, but this work opens the door to further research to understand the relationship between them. Meanwhile, knowing that statins can reduce the risk of dementia following brain shocks, they can encourage older adults to actually use their cholesterol-controlling drugs, Redelmeier noted. Because high cholesterol is predominantly asymptomatic, people often do not take their medication, which puts them at a much higher risk of developing heart disease.