Posttraumatic Stress Disorder-Associated Cognitive Deficits on the Repeatable Battery for the Assessment of Neuropsychological Status in a Veteran Population
Background: Posttraumatic stress disorder (PTSD) is a frequent problem of veterans receiving care and is often associated with cognitive deficits. The Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) is a well-validated cognitive screening measure often used in the US Department of Veterans Affairs (VA), particularly in neurorehabilitation settings. However, the influence of PTSD on RBANS performance is unclear, particularly within a heterogeneous VA outpatient population in which PTSD and traumatic brain injury (TBI) may not be the primary focus of care.
Methods: Participants included 153 veterans with complex deployment-related health problems, including a diagnosis of PTSD (n = 98) and a history of TBI (n = 92). All veterans completed a targeted cognitive battery that included the Wechsler Test of Adult Reading, the Wechsler Adults Intelligence Scale, measure assessing processing speed, attention, and cognitive flexibility, and RBANS.
Results: A diagnosis of PTSD was associated with worse performance on the Story Recall subtest of the RBANS, but not on any other cognitive measures. A diagnosis of mild TBI, or co-occurring PTSD and TBI did not predict cognitive performance on any measures.
Conclusions: The RBANS best captured cognitive deficits associated with PTSD compared with a history of mild TBI or co-occurring mild TBI and PTSD. These findings may provide insight into the interpretation and attribution of cognitive deficits in the veteran population.
Limitations
Several limitations may affect the generalizability of the findings. The present study used a veteran sample referred to a specialty clinic for complicated postdeployment health concerns. Although findings may not be representative of an inpatient population or clinics that focus solely on TBI, they may more adequately reflect veterans using clinical services at VA medical centers. We also did not include measures of PTSD symptom severity (eg, Posttraumatic Stress Disorder Checklist), instead using diagnosis based on the gold standard CAPS. In addition, the likelihood of the presence of a remote TBI was based on a clinical interview with a neurologist and not on acute neurologic findings. TBI is a heterogenous diagnosis, with multiple factors that likely influence cognitive performance, including location of the injury, type of injury, and time since injury, which may be lost during group analysis. Further, the RBANS is not intended to serve as a method for a differential diagnosis of PTSD or TBI. Concordant with this, the intention of the current study was to capture the quality of cognitive function on the RBANS within individuals with PTSD.
Conslusions
The ability for veterans to remember a short story following a delay (ie, RBANS Story Recall subtest) was negatively associated with a diagnosis of PTSD. Further, the RBANS best captured cognitive deficits associated with PTSD compared with those with a history of mild TBI, or co-occurring mild TBI and PTSD. These findings may provide insight into the interpretation and attribution of cognitive deficits in the veteran population and holds potential to guide future research examining focused cognitive phenotypes to provide precision targets in individual treatment.
