Anhedonia and PTSD symptom severity profiles differentially influence physical activity volume in trauma-exposed adults.

Background

It is well-established that adults with elevated psychiatric symptoms or a psychiatric disorder (e.g. depression) engage in lower amounts of physical activity (PA) compared to adults with fewer symptoms/no diagnosis. However, less is known about the association between psychiatric symptoms and PA behaviour in trauma-exposed adults. Most prior investigations have focused on independent associations between overall depression or posttraumatic stress disorder (PTSD) symptoms in relation to PA and have neglected specific symptom domains (e.g. anhedonia). Therefore, we conducted secondary analyses on a parent dataset to examine whether PTSD symptom severity moderates the association between anhedonia and PA volume.

Methods

Trauma-exposed adults (N = 107, 61% women, M ± SD age = 28 ± 9 y 54% White) completed questionnaires assessing demographic information, anhedonia, PTSD symptom severity (overall and symptom clusters), and PA volume (total MET-min/week). Main effects and interactions between anhedonia and PTSD symptom severity in relation to PA volume were examined with robust linear regression models.

Results

We observed a significant anhedonia × PTSD symptom severity interaction. An inverse association between anhedonia and PA volume was observed among adults with lower-to-moderate PTSD symptom severity, and a positive association between anhedonia and PA volume was observed among adults with higher PTSD symptom severity. Significant anhedonia × PTSD symptom severity interactions for avoidance (Cluster C) and negative alterations in arousal/reactivity (Cluster E) symptoms were also observed, with associations in the same direction as the overall PTSD symptom severity model.

Conclusion

These preliminary findings suggest that co-occurring anhedonia and PTSD symptom severity profiles interact to influence PA volume in trauma-exposed adults. Future research is needed to understand why trauma-exposed adults with greater co-occurring anhedonia and PTSD symptom severity profiles reported engaging in higher levels of PA compared to those with lower symptom severity profiles. Such knowledge could help healthcare practitioners tailor treatment plans to incorporate or adjust PA prescriptions.