White Matter Microstructural Changes Due to Chronic Pain and Exposure to Adverse Childhood Experiences in Youth

Introduction: Chronic pain (pain > 3 months) is highly comorbid with adverse childhood experiences (ACEs), PTSD symptoms (PTSS), and altered emotion regulation; however, the mechanisms underlying these relationships remain unclear. We examined whether chronic pain, greater ACEs, and PTSS were associated with decreased white matter connectivity, and whether adaptive emotion regulation was neuroprotective.

Methods: 40 youth, age 14-18 years underwent 3T MRI, and answered questionnaires regarding pain, ACEs, PTSS, and emotion regulation two times, approximately 3 months apart. Diffusion tensor imaging was acquired, and tractography was conducted to obtain mean fractional anisotopy (FA) from regions involved in pain and emotional processing including the: corpus callosum, cingulum, inferior fronto-occipital fasciculus (IFO), superior longitudinal fasciculus (SL), and uncinate. Generalized Estimating Equations were used to compare questionnaires to mean FA, accounting for age, and gender.

Results: Chronic pain and greater suppression were associated with higher mean FA across all tracts (p<0.05), except for left IFO and right SL. Higher ACEs score were associated with higher mean FA of the right SL and left uncinate (p<0.05). Greater PTSS interference was associated with lower mean FA of the right cingulum, and left uncinate (p<0.05). Greater cognitive reappraisal was associated with lower mean FA of the IFO, SL, and left uncinate (p<0.05).

Conclusion: Chronic pain, suppression of emotion and greater exposure to ACEs were associated with greater white matter maturation. Higher cognitive reappraisal may be protective within select brain white matter tracts. Greater PTSS interference may be associated with cell degradation in tracts associated with cognitive and emotional processing.