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Does Brain Injury Increase the Risk for Alzheimer’s Disease?

Categories: Living with Brain Injury

Sustaining a traumatic brain injury (TBI) can have a variety of lifelong impacts and may affect any of the body’s systems. These may be physical, emotional, or cognitive, including, for some individuals, the development of dementia and Alzheimer’s disease.

What is Alzheimer’s disease?

Alzheimer’s is the most common form of dementia, the general term used to indicate memory loss or cognitive changes that seriously impact daily life. According to the Alzheimer’s Foundation, 60-80% of individuals with dementia have Alzheimer’s.

How are Alzheimer’s and TBI related?

Every brain injury is unique. Sustaining a TBI does not mean that an individual will invariably develop any one symptom or associated disease. However, scientific studies spanning more than three decades have established a relationship in some individuals between moderate TBI and Alzheimer’s.

Studies have shown the following:

  • There has been no evidence found that a single, so-called “mild” TBI increases dementia risk.
  • One study found that individuals who had a moderate traumatic brain injury had a 2.3 times increased risk of developing Alzheimer’s, while those who sustained a severe traumatic brain injury were at a 4.5 times greater risk.
  • Individuals who have sustained multiple TBIs have a higher risk of developing Alzheimer’s.
  • Individuals who sustain a brain injury may start experiencing symptoms of cognitive impairment or decline at a younger age.
  • Adults who suffer a brain injury after age 55 have a higher risk of acquiring Alzheimer’s disease.

More research is needed to clarify these results, particularly as relates to the severity of an individual’s TBI and the timing of the onset of dementia symptoms.

What are the symptoms of Alzheimer’s disease?

Alzheimer’s affects cognition, so the primary symptoms are loss of thinking, reasoning, and memory that disrupts daily life.

Examples include:

  • Confusion about time and/or place
  • Forgetting recently learned information
  • Additional effort needed to complete routine tasks
  • Misplacing items Difficulty concentrating

What should I do if I think I may have Alzheimer’s disease as a result of previous brain injury?

Brain injury may immediately change your circumstances and it can also have impacts years after the event itself. If you feel you may be exhibiting new signs of cognitive impairment, regardless of when you sustained a brain injury, or if you are a caretaker for an individual with a brain injury who is exhibiting new symptoms, it is important that you seek professional help.

Don’t know where to start? Contact the National Brain Injury Information Center online or at 1-800-444-6443 to get connected to resources in your area.


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