Schizophrenia-like psychosis following traumatic brain injury: a chart-based descriptive and case-control study

Background. Head injury has been reported to increase the likelihood of the development of schizophrenia-like psychosis (SLP), but its features and ri sk factors have been insufficiently investigated. Method. Between 1987 and 1997, we examined 45 referred patients with SLP fo llowing brain trauma. These subjects were matched with 45 head-injured subj ects without SLP on age (current and at injury) and gender, and their case records reviewed systematically. The groups were compared and logistic regr ession analyses performed. Results. The psychoses had a mean age of onset of 26.3 years, a mean latenc y of 54.7 months after head injury, usually a gradual onset and a subacute or chronic course. Prodromal symptoms were common and depression often pres ent at onset. Paranoid delusions and auditory hallucinations were the predo minant features, with formal thought disorder, catatonic features and negat ive symptoms being uncommon. The SLP group had more widespread brain damage on neuroimaging, especially in the left temporal and right parietal region s, and were more impaired cognitively. Fewer (non-significantly) SLP subjec ts had epilepsy which was more likely to be well-controlled in this group. On regression analysis, a positive family history of psychosis and duration of loss of consciousness were the best predictors of SLP. Conclusions. Head injury-related psychosis is usually paranoid-hallucinator y and subacute or chronic in its presentation. A genetic predisposition to schizophrenia and severity of injury with significant brain damage and cogn itive impairment may be vulnerability factors.