Traumatic brain injury was found to increase the risk for schizophrenia by 33% and bipolar disorder by 78%, according to new study results.
Published in Psychiatry Research, investigators utilized comprehensive data from the Swedish National Registers, analyzing 4,184 cases of schizophrenia and 18,681 cases of bipolar disorder in patients born between 1973 and 1998. By employing a nested case-control design and a sibling comparison method, researchers effectively controlled for genetic and environmental confounders.
The severity of injury played a significant role, with moderate or severe TBIs linked to greater psychiatric risks than mild injuries. Furthermore, the study found risk increased with age at the time of injury, particularly among women.
Detailed statistical analysis, including conditional logistic regression and Cox proportional hazard models, reinforced the findings. Researchers also conducted sensitivity analyses using non-TBI falls as a negative control to test for potential confounding factors, which confirmed the specificity of TBI's impact on psychiatric risks.
Vigilant monitoring and early intervention should be considered for patients with a history of TBI, especially those in high-risk groups identified by the research. This could potentially mitigate the severity of psychiatric outcomes and improve quality of life for patients, noted investigators.
No conflicts of interest were reported. The study was supported by the U.S. National Institute of Mental Health.