A Comparison of Veterans with Post-traumatic Stress Disorder, with Mild Traumatic Brain Injury and with Both Disorders: Understanding Multimorbidity.

Introduction: Mild traumatic brain injury (mTBI) and post-traumatic stress disorder (PTSD) are common military service-related conditions diagnosed both singly and together in veterans returning from recent military conflicts overseas. The impact of these disorders in real-world Veterans Health Administration practice has not been studied extensively, and few studies have examined the association of these disorders both by themselves and together with sociodemographic characteristics, psychiatric and medical comorbidities, health service utilization, and psychotropic medication fills. This study aims to add to the broader study of multimorbidity and the impact it has on patient care.

Materials And Methods: This study used a national Veterans Health Administration sample (N = 164,884) to compare characteristics of veterans diagnosed with mTBI, PTSD, and with both disorders. Relative rates of diagnosis with psychiatric and medical disorders, utilization of medical and psychiatric services, and prescription rates of psychotropic medication fills were examined to determine the impact that the disorders had on these rates, both in isolation and together.

Results: With few exceptions, diagnosis with PTSD, both alone and in the presence of mTBI, was associated with greater risk of comorbid psychiatric diagnosis, higher service utilization, and greater psychotropic medication fills. Notable correlates specific to mTBI included headache, seizure disorder, paraplegia, and cerebrovascular accident.

Conclusion: PTSD thus plays the dominant role in the development of psychiatric difficulties and service use independently of mTBI. The recognition of the central importance of psychiatric difficulties in the functional outcomes of individuals who have experienced an mTBI suggests a need to assure access of veterans to psychiatric treatment services.