Treatment of Fibromyalgia and PTSD With Live and Inactive Vagus Nerve Stimulation With PEPC

Fibromyalgia (FM) pain and PTSD are highly prevalent and comorbid with associated increased risk of negative physical and mental health outcomes, including higher risk for opioid use and suicide. This project is designed to determine the effects of a 4 week trial of a device for pain management \[transauricular vagus nerve stimulation (taVNS)\] on pain interference and intensity \[Pain, Enjoyment, and Activity General Scale (PEG)\] and PTSD. The investigators will also examine how this impacts the Veterans by examining heart rate variability (HRV) as a stress response related biomarker. The investigators plan to randomize 180 Veterans (estimate up to 360 enrolled) with co-morbid FM and PTSD across pain integrated care and PTSD sites in this prospective study and compare: 1) active taVNS for pain + Prolonged Exposure in Primary Care (PE-PC) and 2) sham taVNS + PE-PC. Study includes 4 weeks of randomized treatment and 4 weeks of voluntary open label treatment. Veterans are assessed (self report \& interview measures, heart rate variability by wearable device) at Intake, Baseline/Post Run-In, Week 2, Week 4, Week 8 and 4 month follow-up. The investigators plan to retain data after the study for potential future use in research.

Inclusion Criteria: 1. Subjects must be any era Veterans reporting FM and PTSD symptoms (PTSD Checklist for DSM-5 (PCL-5) ≥ 28; FM confirmed with ACR Diagnostic Criteria and pain score at least 4/10 for 3 months \[94\] 2. Subjects must speak English 3. If subjects are taking psychotropic medication, 2-weeks on stable dose prior to enrollment and agreement to maintain current medications until after the \[4-month follow-up visit\] Exclusion Criteria: 1. Subjects must not have other primary clinical issues that would interfere with FM or PTSD treatment such as recent stroke or severe heart disease 2. Subjects must not have a level of suicide risk that requires intervention as determined by item 9 on PHQ-9 with follow-up risk assessment by study staff 3. Subjects must not have severe cognitive impairment that interferes with PE-PC (unable to retain information in acute interaction) 4. Subjects must not have unmanaged psychosis or bipolar disorder 5. Subjects must not have moderate to severe substance use disorder in the past 8 weeks 6. Subjects must not be currently receiving talk therapy for trauma-related symptoms or FM 7. Subjects must not be currently pregnant or lactating given risk of pre-term labor and interference of oxytocin with VNS effects