Objective: To examine the preinjury rates of Axis I disorders and the prospective rates within the first 6 years after traumatic brain injury (TBI).
Design: Cross-sectional, longitudinal, and cross-sequential.
Setting: Community-based research and training center.
Participants: Persons (N=188) who had sustained TBI within 4 years of enrollment into the project were interviewed at either 2 and 3 assessments. Each assessment was approximately 1 year apart. Several Axis I diagnoses were analyzed to detect cross-sectional differences (by age and time postinjury) and average individual changes over the multiple measurement time points.
Interventions: Not applicable.
Main outcome measure: Structured Clinical Interview for the Diagnostic and Statistical Manual of Mental Disorders.
Results: The odds ratios changed longitudinally within each subject, indicating a decreased probability of having an Axis I diagnosis over time. There were few cross-sectional differences in age; therefore, age at the time of injury had little impact on Axis I diagnoses. Cross-sectional time since injury was not associated with more psychiatric disorders, whereas cross-sectional preinjury history of psychiatric disorders was predictive of postinjury psychiatric disorders. After controlling for cross-sectional effects, the frequencies of Axis I disorders increased in depression, anxiety, and posttraumatic stress disorders in the first assessment postinjury and declined in subsequent assessments.
Conclusions: Cross-sequential analyses that control for cross-sectional and longitudinal differences produced a more complete description of psychiatric disorders after TBI.