Relationships of Affect and Neuroinflammation With Clinical Pain in Veterans With Fibromyalgia

Fibromyalgia (FM) is a chronic pain condition that disproportionately impacts Veterans. Individuals diagnosed with FM patients experience lower self-esteem and positive affect, as well as greater levels of depression, anxiety, negative affect, and pain catastrophizing. Among those experiencing FM, clinical and experimental pain are associated with specific dispositional trait profiles, which are indexed by levels of negative affect and positive affect. Neuroinflammation and inflammation also play a role in FM- related affect and pain. Recent studies that have highlighted neuroinflammation and inflammation as physiological mechanisms associated with changes in dysregulated affect and chronic pain. Veterans with FM can ameliorate their dispositional traits-i.e., increasing positive affect and reducing negative affect-by participating in exercise. However, a gap exists regarding how to optimally engage Veterans with FM in an exercise program. Thus, to fully take advantage of all potential therapeutic benefits of exercise for FM, there is a critical need to identify those factors underlying exercise engagement for FM pain management. The purpose for this study is to 1) determine associations of dispositional trait styles, neuroinflammation, and inflammation with pain outcomes in Veterans with FM; and 2) develop and design a Veteran-informed exercise program.

The investigators propose to recruit 20 Veterans with FM and 20 Veterans without FM who will undergo magnetic resonance spectroscopy imaging (MRSI) scans, pain assessments, and semi-structured interviews. They will undergo a 6-week moderate intensity continuous training exercise intervention and follow-up MRSI scans, pain assessments, and semi-structured interviews. The investigators central hypothesis is that dispositional trait styles, neuroinflammation, and inflammation will be associated with pain outcomes and exercise will induce beneficial anti-inflammatory changes. The research objective of this proposal is two-fold: 1) to acquire data on the associations between dispositional trait styles, neuroinflammation, inflammation, and pain in Veterans with FM and 2) to develop a Veteran-informed exercise program with potential to modify dispositional trait styles, neuroinflammation, inflammation, and pain in Veterans with FM.

Eligibility Criteria:
Inclusion Criteria:

Inclusion Criteria for Veterans living with FM:

* Inclusion Criteria (FM)(1) Age 19 years or older;
* Widespread pain index (WPI) 7 and symptom severity scale (SSS) score 5 OR WPI 4-6 and SSS score 9;
* Generalized pain, defined as pain in at least 4 of 5 regions, is present;
* Symptoms have been present at a similar level for at least 3 months;
* A diagnosis of FM is valid irrespective of other diagnoses. A diagnosis of FM does not exclude the presence of other clinically important illnesses;
* PTSD Checklist-Stressor-Specific Version 1 re-experiencing (intrusion) symptom, 3 avoidance (numbing) symptoms, and 2 hyperarousal symptoms, each present at the level of moderate or higher during the past month, and if their total severity score is 50 or higher.

Inclusion Criteria for Veterans living without FM:

(1) Age-matched to participant with FM.

Exclusion Criteria:

Exclusion Criteria for Veterans living with FM:

* Neurological disorder
* Body mass index \> 40
* Chronic kidney disease
* Severe cardiac condition (chronic heart failure, stenosis, history of cardiac arrest, defibrillator, angina)
* Ischemic heart disease
* 90 days of daily opioid use
* Beta-blocker
* Inability to consent for study participation (9) Significant cognitive impairment, defined as a known diagnosis of dementia (10) MRI contraindications (11) Pregnancy

Exclusion Criteria for Veterans living without FM:

1. Active use of medications affecting pain responses
2. Neurological disorder
3. Body mass index \> 40
4. MRI contraindications
5. Pregnancy