The Effect of Autoreactive Autoantibodies on Peripheral and Central Disease Mechanisms in Fibromyalgia.

NCT07346950 | Completed DMC

• 1 other identifier: 2022-03464-01
• Study Type: observational
• Target: 164
• Locations: 1 country
• Sites: 1

Brief Summary

This observational study aims to compare disease burden and pain characteristics between fibromyalgia patients with high levels of autoreactive autoantibodies, fibromyalgia patients with low levels of autoreactive autoantibodies, and healthy controls. The primary hypothesis is that patients experience more symptoms (as measured with questionnaires) depending on their antibody titer, and that high levels of autoantibodies correlate with other biological markers, such as inflammatory profile in serum, and density of intraepidermal nerve fibers in skin. The secondary aim of this study is to characterize central markers of disease, which will be done using a number of methods: the investigators will quantify immune profile in the cerebrospinal fluid, measure thalamic neurotransmitter levels with magnetic resonance spectroscopy (MRS), blood-brain barrier permeability with both biochemical markers and T1-weighed gadolinium-enhanced magnetic resonance imaging (MRI), and resting state activity of the brain (MRI). The investigators hypothesize that there are signs of upregulation of the immune system of the central compartment, and that this will be correlated with altered neurotransmitter levels and an altered resting state activity.

Conditions

Fibromyalgia

Keywords

cytokines; neuroinflammation; blood-brain barrier; BBB; fMRI; autoantibodies; skin; MRS; cerebrospinal fluid

Outcome Measures

Primary Outcomes (1)

• Anti-SGC antibodies

  Autoantibodies that bind to satellite glia cells in the dorsal root ganglia. The investigators hypothesize that autoantibody titers are associated with symptom severity (Goebel et al., 2021; Krock et al., 2023; Fanton et al., 2023), changes in inflammatory profile (af Ekenstam et al., 2025) and alterations in skin histological findings.

  At study inclusion.

Secondary Outcomes (9)

• Neurotransmitter levels in the right thalamus

  At study inclusion.

• Inflammatory profile in serum

  At study inclusion.

• Inflammatory profile in cerebrospinal fluid

  At study inclusion.

• CSF-serum albumin quotients

  At study inclusion.

• Quantitative sensory testing (QST)

  At study inclusion.

Study Arms (3)

FM

Participants with fibromyalgia according to the ACR 1990+2016 criteria.

HC

Control participants that have no pain condition. No cerebrospinal fluid was collected from this cohort.

CSF controls

A cohort consisting of 1) healthy controls (n = 11) recruited in another study and 2) patients with non-inflammatory neurological symptoms (NINS, n = 32) that underwent clinical workup at the neurological clinic at Uppsala University Hospital.

Eligibility Criteria

• Age: 20 Years - 70 Years
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

In total, 80 subjects with fibromyalgia (FM) and 42 healthy controls (HC) will be included. Subjects predominantly live in Uppsala County, Sweden, which has a population of approximately 400,000 inhabitants. If we consider the prevalence of FM to be 2%, that translates to \~8,000 patients. Since the study is on female subjects, and about 70% of FM patients are female, that leaves about 5,600 patients in the pool. The sample size has been determined based on previous research where a group size of 40 subjects was deemed sizeable enough to identify meaningful differences in expression of proteins. As we are interested in two groups of FM patients, i.e., those with high and low levels of autoreactive autoantibodies, and we expect about 50% of participants with FM to have high titers, we will require about 80 participants in the FM group. For the NINS cohort, the biobank of the neurological clinic at Uppsala University Hospital will be utilized to find appropriate CSF controls.

You may qualify if:

• Female sex
• Age 20-70
• Fibromyalgia according to the ACR 1990+2016 criteria for the FM cohort.

You may not qualify if:

• Reported BMI \> 35 during screening over a phone call.
• Other dominant chronic pain states.
• Autoimmune diseases (exception: primary hypothyroidism).
• Serious somatic or psychiatric disease.
• Current pregnancy.
• Non-fluency in Swedish.
• For HC: history of chronic pain or current pain exceeding 20 on a 0-100 scale or having received an FM diagnosis.
• For NINS: having received an FM diagnosis.

Sponsors & Collaborators

• Uppsala University: lead

Study Sites (1)

Uppsala University Hospital

Uppsala, Sweden

Location

Biospecimen

Retention: SAMPLES WITH DNA

Skin (4mm punch biopsy) Serum Plasma Peripheral blood mononuclear cells Cerebrospinal fluid cells

MeSH Terms

Conditions

Fibromyalgia; Neuroinflammatory Diseases

Condition Hierarchy (Ancestors)

Muscular Diseases; Musculoskeletal Diseases; Rheumatic Diseases; Neuromuscular Diseases; Nervous System Diseases; Inflammation; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Officials

• Eva Kosek, MD, PhD

  Uppsala University, Karolinska Institutet

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: CROSS SECTIONAL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: December 3, 2025
• First Posted: January 16, 2026
• Study Start: November 30, 2022
• Primary Completion: June 11, 2025
• Study Completion: December 18, 2025
• Last Updated: January 16, 2026

Record last verified: 2026-01

Locations

SE (1)