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

The investigators' goal is to test whether providing simultaneous non-drug treatments for both FM and PTSD improves symptom impact on both conditions. taVNS, a non-invasive neuromodulatory technique applied to the auricular branch of the vagus nerve, has preliminary efficacy in reducing chronic pain and reducing PTSD severity in Veterans with PTSD and in an opioid withdrawal population. PE-PC is a form of Prolonged Exposure, a gold standard treatment for PTSD, that is designed for integrated care and effectively reduces PTSD severity. In addition, taVNS applied with the proposed device significantly reduced PCL-5 scores by 35% from baseline to Day 5 in adults withdrawing from opioid. Within this high-risk comorbid population, adding a non-opioid pain intervention provided within the context of effective PTSD treatment promises to increase impact on both pain and PTSD. The combination requires minimal additional 'in clinic' time, may be provided in-home or via telehealth, and each is available in VA standard care. Study results can inform implementation for this combined intervention and speed its use in clinics. Thus, more Veterans will have access to effective care for FM and PTSD, supporting a priority of POU-AMP and the VA National Strategy for Preventing Suicide (2018). In summary, the investigators will examine whether pain is reduced with PTSD treatment in FM, and whether addition of taVNS can augment this effect compared to sham.

Design: The investigators will randomize 180 Veterans with co-morbid FM and PTSD from across AVAHCS to receive: 1) taVNS for pain + PE-PC or 2) sham taVNS + PE-PC. taVNS administered daily for 2 hours for 4 weeks. PE-PC is provided in six 30-minute sessions up to 3 times per week. Assessments will be collected at Intake, Baseline/Post Run-In, Week 2, Week 4, and [4 month follow-up]. Primary outcome will be posttreatment (week 4) Pain, Enjoyment and General Activity Scale (PEG). Secondary outcomes include Fibromyalgia Impact Questionnaire Revised (FIQR), Polysymptomatic Distress Scale (PSD), PTSD (PCL-5 weekly version). Biomarker analysis will examine the association of HRV [(baseline & trauma cued).

Aim (1): Examine additive efficacy of 1) taVNS+PE-PC and 2) sham taVNS+PE-PC on FM-related pain interference and intensity in the context of PE-PC for PTSD [Primary Outcome: PEG scale and PTSD symptom severity [Secondary Outcome: PCL5, weekly].

Hypothesis 1a: taVNS+PE-PC will result in larger reductions in pain interference and intensity than sham taVNS+PE-PC ([Baseline] to Week 4). Differences will be maintained at [4-month follow-up].

Hypothesis 1b: taVNS+PE-PC will result in larger reductions in PTSD severity than sham taVNS+PE-PC ([Baseline] to Week 4). Differences will be maintained at [4-month follow-up].

Exploratory Aim: Evaluate changes in HRV (baseline & trauma cued) as a biomarker of response associated with FM-related pain and PTSD severity improvement in taVNS+PE-PC and sham taVNS+PE-PC.

Exploratory Hypothesis: taVNS+PE-PC will result in greater change in HRV compared to sham+PE-PC. This proposal targets the Pain and Opioid Use Actively Managed Portfolio (POU-AMP) research priority of pragmatic clinical trials for treatment of painful conditions using non-pharmacological approaches. The long-term objective is improving Veteran health through focused combined intervention for FM and PTSD.

Inclusion criteria

• 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]
• Subjects must speak English
• 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

• Subjects must not have other primary clinical issues that would interfere with FM or PTSD treatment such as recent stroke or severe heart disease
• 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
• Subjects must not have severe cognitive impairment that interferes with PE-PC (unable to retain information in acute interaction)
• Subjects must not have unmanaged psychosis or bipolar disorder
• Subjects must not have moderate to severe substance use disorder in the past 8 weeks
• Subjects must not be currently receiving talk therapy for trauma-related symptoms or FM
• Subjects must not be currently pregnant or lactating given risk of pre-term labor and interference of oxytocin with VNS effects