Fann, J, Burrington B, Leonetti A, Jaffe K, Katon W, Thompson R. Abstract of psychiatric illness following traumatic brain injury in an adult health maintenance organization population.Arch General Psychiatry.2004;61(1):53-61.

The purpose of this study was to determine the prevalence of psychiatric illness following traumatic brain injury (TBI) in an adult HMO population. The study was based on computerized records from a large Seattle HMO. Criterion for establishing evidence of psychiatric illness was presence of a psychiatric diagnosis, filling of a prescription for psychiatric medication, or utilization of psychiatric serves. Time frame was 1 year prior to injury and 3 years postinjury.

A total of 49% of 939 subjects with moderate-to-severe TBI had evidence of a psychiatric illness in the year following injury, compared with 34% of those with mild TBI and 18% of non-TBI comparison groups. Those with a prior history of psychiatric illness had a higher incidence of psychiatric illness following injury. The risk of psychiatric illness was greatest in the first 6 to 12 months following injury.

Implication of this study is the need to monitor TBI patients for psychiatric illness, especially those with a history of prior psychiatric illness.