Verbal Memory in Traumatic Brain Injury: Associations With Age, Post-traumatic Stress Disorder, and Antidepressant Use.

OBJECTIVE

Episodic memory is one of the cognitive domains most affected after a traumatic brain injury (TBI), and memory decline is a hallmark of both normal aging and Alzheimer disease (AD). Although TBI is reported to accelerate age-related cognitive decline and brain atrophy, it is unclear how this trajectory is shaped by frequent co-occurring factors such as post-traumatic stress disorder (PTSD) and psychotropic medication use. This study tested whether age-related decline in delayed verbal memory is more pronounced among adults with a history of TBI than those without TBI. Analyses also explored PTSD status and use of selective serotonin reuptake inhibitors or serotonin-norepinephrine reuptake inhibitors (SSRIs/SNRIs) as independent moderators of verbal memory performance.

SETTING

VA Medical Center and surrounding community.

PARTICIPANTS

Sixty-two Veterans and civilians, ages 30-65, were enrolled. Participants who performed below established cutoffs on performance validity testing were excluded. Analyses (n = 56) included 28 adults with a history of TBI (82% mild, 18% moderate) and 28 demographically matched controls without TBI.

MAIN MEASURES: Delayed recall on a standardized verbal memory task was the primary outcome measure. Analyses tested for main effects of TBI status, age, and their interaction, as well as interactions with the moderator variables (PTSD status and SSRI/SNRI use).

DESIGN

Observational, cross-sectional design.

RESULTS

Participants with a TBI history did not significantly differ from those without TBI in verbal memory performance. There was a trend toward poorer memory performance with age among participants with a TBI history not taking SSRIs/SNRIs, while participants with PTSD and TBI taking SSRIs/SNRIs demonstrated better performance with age.

CONCLUSION

The findings underscore the importance of considering psychiatric comorbidities and medication use when examining cognition and aging effects in individuals with TBI. Larger, longitudinal studies are warranted to clarify how traumatic stress and psychotropic medications may mediate cognitive aging trajectories after TBI.