It might seem like a minor injury, but suffering a fall could dramatically raise your risk of dementia, a study suggests.

In Canada, researchers observed 260,000 older individuals over a period of up to 17 years. Among them, half experienced a traumatic brain injury (TBI), which is often a result of falls that involve the head impacting the ground, potentially leading to bruising or bleeding in the brain.

Overall, researchers found those who sustained the injury from any cause had a 69 percent higher risk of being diagnosed with dementia within the next five years compared to those who did not suffer the head trauma.

The researchers did not say whether the participants were suffering TBIs because of falls specifically, although this is the most common reason for the complication in older adulthood, behind 80 percent of cases, according to estimates.

After more than five years, TBI sufferers also had a 56 percent higher risk of a dementia diagnosis than those who never experienced the damage.

Dr Yu Qing Huang, a geriatrician at the University of Toronto who led the study, said: ‘One of the most common reasons for TBI in older adulthood is sustaining a fall, which is often preventable.

‘By targeting fall-related TBIs, we can potentially reduce TBI-associated dementia [among older adults].’

The study authors did not suggest why the injury raised the risk of dementia, but in previous research, scientists have said it may be because of damage to brain cells, triggering a buildup of abnormal proteins linked to the dementia. 

Researchers in Toronto found that suffering a traumatic brain injury in older age, often linked to a fall, raised the risk of being diagnosed with dementia (stock image)

It’s also been suggested it may be because patients who suffer the injury already have undiagnosed dementia or mild cognitive impairment (MCI), a precursor to dementia.

Dementia and MCI are known to raise the risk of suffering from a fall or TBI, which may then speed the advancement of the disease.

About 14million Americans, or one in four, aged 65 years and older, suffer from a fall every year, with up to 60 percent of these resulting in a TBI.

And Alzheimer’s disease is the most common form of dementia, suffered by about 7million people a year, with cases estimated to reach 13million by 2050. 

Falls are the most common cause of TBI for older adults, but they can also be caused by car accidents or head trauma.

In milder cases, sufferers may lose consciousness for a few seconds to a minute, have temporary memory or concentration issues, or be dizzy and lose balance again.

In moderate to severe injuries, patients may lose consciousness for several minutes to hours, and then experience persistent headaches, confusion, agitation and slurred speech.

They may also cause personality changes and, at times, lasting disabilities such as memory loss, difficulty with concentration and slower processing.

It is unclear how often TBIs are mild versus moderate or severe, although a World Health Organization review previously found that about 70 to 90 percent of all TBIs were mild in nature. 

The above shows the percentage of participants who developed dementia (Y axis, or vertical axis) by time in years (X axis, or horizontal axis). It shows people who suffered from a traumatic brain injury were more likely to be diagnosed with dementia

This is just the latest study to find a link between a TBI and a higher risk of dementia, after a 2024 paper showed adults over 65 years old who suffered from a fall were 20 percent more likely to be diagnosed with dementia a year later than their peers.

For the study, published in the Canadian Medical Association Journal, researchers analyzed data from health administrative databases in Ontario, Canada.

They looked at adults aged 65 years and older who had suffered a traumatic brain injury between April 2004 and March 2020 from any cause and compared them to similar people who had not suffered the head trauma.

Participants were followed until they were diagnosed with dementia, the study’s end in March 2021 or had died.

In addition to the increased risk of dementia, researchers also found that, overall, about one in three people aged 85 years or older who suffered from a TBI would develop dementia.

Of the groups analyzed, those who were female and 75 years or older were found to be most at risk of the dementia diagnosis after a TBI.

This may be because women live longer than men, and are more likely to suffer from muscle weakness, osteoporosis or dementia, raising the risk of a fall.

The above is a CDC map showing the states that report the most and least falls among older adults

The study also showed that patients who were older, lived in small communities, and in areas with low income and ethnic diversity were the most likely to be admitted to a nursing home after suffering from a TBI.

It was not clear why the risk of being diagnosed with dementia after suffering from a TBI dropped slightly after five years, although this may be because the brain has managed to repair the initial damage from the injury, possibly slightly lowering the risk of dementia.

Dr Huang added: ‘Our findings suggest that, to better align limited health resources with population needs, specialized programs such as community-based dementia prevention programs, and support services should be prioritized for female older adults (over 75 years old) living in smaller communities and low-income and low-diversity areas.’

And the authors added: ‘Although TBI has been studied as a risk factor for dementia in adulthood, our findings emphasize its significant association with an increased rate of incident dementia, even when it is sustained in late life, and how this risk changes over time.

‘This is critical information [that] can assist clinicians in guiding older patients and their families to better understand long-term risks.’