Protocol for a Diagnostic Test Accuracy of Histological Muscle and Skin Biopsies of Rheumatoid Arthritis Patients Revealing Objective Chronic Widespread Pain Phenomena Related to Fibromyalgia

Brief summary (from the registry)

Background: Chronic widespread pain is challenging in the management of the patient with rheumatoid arthritis (RA), affecting approximately one third of this patient population. However, pain is not always caused by disease activity (inflammation) but can be associated to central pain mechanisms as seen in fibromyalgia (FM). FM is characterized by widespread pain and tenderness; often accompanied by disturbed sleep, fatigue, cognitive impairment, emotional distress and multiple symptoms from various organ systems. Among patients with RA the prevalence of concomitant FM is reported to be 12-17% compared to 1-3% in the general population. In general the pain, felt by the fibromyalgia patients is considered to be due to lower pain thresholds because of abnormal central pain processing. Pain reported by RA patients with concomitant FM could potentially be explained by this phenomenon. Little is known about RA patients fulfilling criteria for FM. Muscles-studies of FM patients have not found any histopathological explanation of the pain felt, however an old study of muscle changes in RA patients found changes that could explain muscle pain. Small fiber neuropathy (SFN) is a condition associated with autoimmune diseases, and evidence suggests that SFN is likely to contribute to the pain observed in FM. Objectives: To determine the diagnostic test accuracy (sensitivity and specificity) of both muscle- and skin-biopsies for fibromyalgia phenotyping and detection by clinical referral (RA with concomitant FM) as the reference standard (i.e. fulfilment of 2016 FM criteria). Data collection: Will be done as study subjects are included and stored in REDCAP. Eligibility criteria for participants and settings where the data will be collected: RA patients will be assessed in the daily clinic in Esbjerg and Odense and examined for concomitant FM (I.e. satisfying the 2016 criteria for FM). Patients will afterwards be invited to participate in the study. Inclusion will continue until …

Study details

Official title

Diagnostic Test Accuracy of Histological Muscle and Skin Biopsies of Rheumatoid Arthritis Patients Revealing Objective Chronic Widespread Pain Phenomena Related to Fibromyalgia

Conditions

• Rheumatoid Arthritis
• Fibromyalgia, Secondary
• Widespread Chronic Pain
• Muscle Disorder

Interventions

• Diagnostic test: Muscle- and skin biopsies

Sponsor

Esbjerg Hospital - University Hospital of Southern Denmark

Collaborators

Odense University Hospital

Start date

2024-02-07

Primary completion

2024-11-22

Sex

All

Age range

from 18 Years to 100 Years

Results posted

No results posted in this snapshot

Countries

Denmark

Total sites listed

1

Eligibility criteria