Mild traumatic brain injury and posttraumatic stress disorder and their associations with health symptoms.

OBJECTIVE: To determine the association of various symptoms and psychiatric diagnoses with a remote history of mild traumatic brain injury (MTBI) and a current diagnosis of posttraumatic stress disorder (PTSD).

DESIGN: Cross-sectional cohort study.

SETTING: Nonclinical.

PARTICIPANTS: Three groups of randomly selected community dwelling male U.S. Army Vietnam-era veterans: healthy control (n=3218), those injured in a motor vehicle collision (MVC) but without a head injury (MVC injury control; n=548), and those who had an MTBI (n=278).

INTERVENTIONS: None.

MAIN OUTCOME MEASURES: Prevalence of psychiatric diagnoses, physical, cognitive, and emotional symptoms, and course of PTSD across time.

RESULTS: Logistic regression procedures were used to determine group association with symptoms and psychiatric diagnosis after controlling for demographic variables, combat intensity, medical disorders, and other current psychiatric conditions. MTBI was associated with headaches, memory problems, sleep problems, and fainting even after controlling for current psychiatric problems (including PTSD), as well as demographic variables, combat intensity, and comorbid medical conditions. MTBI also was associated with a current diagnosis of PTSD even controlling for other demographic, psychiatric, and medical covariates. MTBI did not moderate or mediate the relationship between PTSD and current symptomatology. However, MTBI did adversely affect long-term recovery from PTSD (odds ratio=1.59, 95% CI, 1.07-2.37). PTSD also was associated with physical, cognitive, and emotional symptoms, and had a larger effect size than MTBI.

CONCLUSIONS: MTBI, even in the chronic phase years postinjury, is not a benign condition. It is associated with increased rates of headaches, sleep problems, and memory difficulties. Furthermore, it can complicate or prolong recovery from preexisting or comorbid conditions such as PTSD. Similarly, PTSD is a potent cocontributor to physical, cognitive, and emotional symptoms.