Autonomic variability, depression and the disability paradox in spinal cord injury.

STUDY DESIGN

Longitudinal.

OBJECTIVE

With an increased risk of depression in spinal cord injury, the study longitudinally examines depression to understand how post-injury autonomic regulation and coping might be related to somatic and cognitive manifestations of depression after 3 years.

SETTING

Indian Spinal Injuries Center.

METHODS

Twenty-eight spinal cord injury participants completed the follow-up assessment of the Patient Health Questionnaire 3 years post-injury. The participants were grouped based on post-injury autonomic regulation (high and low HRV) and the somatic and cognitive manifestation of depression reflected in a depression ratio. Wilcoxson signed-rank test tested the post-injury (T1) and 3 year follow-up (T2) depression scores.

RESULTS

Depression score reduced after 3 years of injury (p ≤ 0.05). Only the high HRV group showed a higher depression ratio (somatic/ cognitive) atfollow-up (T2) (p ≤ 0.05). No difference was observed in post-injury coping between high and low HRV groups.

CONCLUSION

The reduced depression score at follow-up (T2) aligns with the 'disability paradox' and mightindicate cognitive adaptation, specifically for those who showed autonomic adaptability in the form of post-injury high autonomic variability.