Link Between TBI and Mental Illness

November 2, 2016

Victims of traumatic brain injuries (TBIs) and their families have to deal with a wide range of devastating adverse health effects. From memory loss to cognitive difficulties, TBI patients can suffer the effects of their injuries for years. Some never fully return to their prior mental state. While doctors have acquired plenty of information about the link between TBI and cognitive/behavioral problems, a relatively new discovery is the connection between TBI and mental illness.

The Aftermath of a TBI

After sustaining a head injury, the brain’s blood vessels may stretch and damage the cranial nerves, resulting in concussion. During a TBI, a victim may or may not lose consciousness. If a victim remains conscious, he or she may experience dizziness, nausea, blurred vision, confusion, or memory loss. Loss of consciousness points to a more severe TBI with more dramatic symptoms. A severe TBI can put the victim in a coma or result in permanent cognitive dysfunction and disability. New studies show that brain damage repercussions may also contribute to the development of mental illness.
Inflammation and disrupted neurotransmitters in the brain may be the cause of the correlation between TBIs and mental illnesses. Most head traumas cause the brain to swell and push against the inside of the skull, leading to brain injury. This can destroy an area of the brain, eventually contributing to the development of a mental disorder associated with this area. Another possible cause of this connection is the emotional and mental trauma a victim suffers in an accident. Psychological and emotional repercussions of an accident could trigger a mental disorder.

Clear Connection Between TBI and Mental Illness

Danish scientists have found that a head injury can increase the risk of developing a mental disorder by up to 439%. This correlation is stronger than previously suspected and further complicates personal injury cases involving TBIs. Now, victims of head injuries and TBIs can potentially sue for the probability of developing a mental illness down the road. The study is the largest of its kind. Researchers followed 113,906 head injury patients from 2000 to 2010. The study found that doctors subsequently diagnosed 4% (about 4,556 people) of these patients with mental disorders.
Mental illnesses connected to TBIs and head injuries include bipolar disorder, schizophrenia, and depression. The majority of head injury victims developed a mental illness within one year of the time of injury, but the significantly-increased risk lasts as long as 15 years. According to the study, victims of head injuries were:

  • 28% more likely to develop bipolar disorder.
  • 59% more likely to develop depression.
  • 65% more likely to develop schizophrenia.
  • 439% more likely to suffer organic mental disorders.

There is a “chicken or the egg” dilemma in which scientists can’t tell whether the head injury caused the mental illness or if it’s the other way around. The Danish study tried to address this problem by researching other injuries for increased the risk of mental disorders. They found a slight correlation between injuries such as broken bones and mental illness, but nothing nearly as significant as the connection with head injuries.

TBI and Schizophrenia

Scientists have long-since established the connection between TBIs and psychiatric conditions. It wasn’t until the 1990s, however, that scientists began to explore the link between TBI and schizophrenia in earnest. Studies have since shown that patients with a family history of schizophrenia are more at risk of developing the condition after a TBI.
In most cases, TBI patients developed schizophrenia within two years of the accident. Some evidence does show that a TBI may damage areas of the brain that control dopamine and higher functions, leading to psychosis. As scientists learn more about TBIs and mental illnesses, the chances of finding reliable and effective treatment options increase.