High risk of head injury after diagnosis of psychiatric illness

Patients with evidence of recent psychiatric illness have a high risk of sustaining head injury over the next 12 months, finds a study in the Journal of Neurology Neurosurgery and Psychiatry.

The researchers looked at the health records of patients who had sustained a head injury in the 12 months after joining a large health organisation (HMO) in the USA covering six counties.

The presence of mental health problems was determined from prescriptions for psychiatric drugs, a confirmed psychiatric diagnosis, and use of psychiatric services.

They found 1440 patients with head injuries for whom complete records were available. Those with mental health problems in the preceding 12 months were 60 per cent more likely to sustain a head injury than those without these problems. The authors calculated that almost one in 10 injuries might be attributable to a psychiatric illness.

Most patients had internal head injuries. The remaining 5 per cent had fractures. Almost half the patients were 19 or younger.

Those with a diagnosis of organic non-psychotic disorders, such as dementia and delirium, had the greatest risk of head injury,. Patients taking drugs for anxiety and psychosis were over twice as likely to sustain a head injury, while antidepressants were also associated with a significantly increased risk.

Acute stress reactions, drugs or alcohol misuse, malaise and fatigue also increased the risk of sustaining head injury compared with those who did not suffer from these conditions.

The authors conclude that patients with an indicator of psychiatric illness are at increased risk of head injury, which even if mild may result in major disability.