Traumatic Brain Injury and Schizophrenia in Members of Schizophrenia and Bipolar Disorder Pedigrees

Members of the schizophrenia pedigrees, even those without a schizophrenia diagnosis, had greater exposure to traumatic brain injury compared to members of the bipolar disorder pedigrees. Within the schizophrenia pedigrees, traumatic brain injury was associated with a greater risk of schizophrenia, consistent with synergistic effects between genetic vulnerability for schizophrenia and traumatic brain injury. Posttraumatic-brain-injury schizophrenia in multiplex schizophrenia pedigrees does not appear to be a phenocopy of the genetic disorder.