The moderating role of psychological resilience on brain aging and PTSD in a community sample of South African women

Posttraumatic stress disorder (PTSD) is associated with accelerated biological aging. In general, psychological resilience is related to more normative aging patterns; however, among individuals with PTSD, resilience may be associated with older biological aging. For example, prior work suggests that individuals with PTSD who have higher psychological resilience show more advanced epigenetic aging than individuals with lower psychological resilience. We investigated whether psychological resilience moderated the relationship between PTSD and brain aging in a community sample of South African women. Individuals (N = 189) were recruited as part of the Drakenstein Child Health Study. Participants underwent a structural MRI and completed questionnaires of PTSD (modified-PTSD Symptom Scale, mPSS) and psychological resilience (Connor-Davidson Resilience Scale; CD-RISC). Using a pre-trained model, a predicted brain age gap was derived. Linear models tested a CD-RISC x Group (no trauma exposure (NTE), trauma-exposed [TE], and PTSD) interaction on brain age gap. Follow-up models probed regional brain age gap (e.g., subcortical, frontal, parietal). There was no main effect of Group on brain age gap. There was a significant CD-RISC x Group interaction, such that higher CD-RISC scores were associated with a positive brain age gap (reflecting an older appearing brain) only in women with suspected PTSD but not in NTE or TE individuals. Follow-up tests showed the CD-RISC x Group interaction was only significant in the subcortical region, suggesting the effect was driven by alterations in subcortical structures frequently implicated in PTSD. Future longitudinal work should examine whether psychological resilience moderates PTSD-related brain aging across time.