Fibromyalgia and Small Fiber Neuropathy

NCT06527183 | Recruiting

• 1 other identifier: 2020-A03400-39
• Study Type: observational
• Target: 150
• Locations: 1 country
• Sites: 2

Brief Summary

The primary objective of this study will be to assess the proportion of fibromyalgia patients with diffuse small-fiber neuropathy (i.e. in the upper and lower limbs) and compare this proportion to patients with other chronic pains (nociplastic, nociceptive) and with healthy controls. Our analysis will be based on the demonstration of structural abnormalities of small nerve fibers by means of skin biopsy, but also of functional abnormalities using four validated tests commonly used in this field: quantitative sensory testing (QST), laser evoked potential recordings, Sudoscan and confocal corneal microscopy. It will thus be possible to verify whether or not patients with small fiber neuropathy have a particular clinical profile in terms of pain, physical activity, comorbidities or pain impact.

Conditions

Chronic Pain Syndrome

Outcome Measures

Primary Outcomes (1)

• Prevalence of small fiber neuropathy or pathology as assessed with skin punch biopsy in patients with fibromyalgia as compared to patients with other chronic pains and healthy subjects

  intraepidermal nerve fiber density

  Baseline and at 6 months

Secondary Outcomes (5)

• Correlation between intraepidermal nerve fiber density and pain or other patient reported outcome measures (quality of life, distress, disability...)

  Baseline and at 6 months

• Investigate the potential specificity of the results obtained by comparing them with pain patients without fibromyalgia or nerve damage (patients with any nociceptive or nociplastic pain without fibromyalgia) matched for age and gender

  Baseline and at 6 months

• Monitor the evolution of abnormalities obtained over time (6 months) and correlate them with the evolution of pain and associated symptoms.

  6 months

• Determine the sensitivity and diagnostic value of corneal confocal microscopy and laser evoked potentials as compared with skin punch biopsy for exploring nociceptive fibers

  Baseline and at 6 months

• Determine the diagnostic value of the sudoscan and quantified sensory tests compared with other tests for exploring nociceptive fibers in these patients

  Baseline and at 6 months

Study Arms (3)

Patients with fibromyalgia

Patients with fibromyalgia based on ACR criteria

Diagnostic Test: Skin punch biopsy to demonstrate small fiber neuropathy

Patients with other chronic pain (paired for the other groups)

Patients with chronic pain other than fibromyalgia and neuropathic pain, eg nociplastic pains or nociceptive pains

Diagnostic Test: Skin punch biopsy to demonstrate small fiber neuropathy

Paired healthy subjects

Healthy subjects paired for gender and age

Diagnostic Test: Skin punch biopsy to demonstrate small fiber neuropathy

Interventions

Skin punch biopsy to demonstrate small fiber neuropathy DIAGNOSTIC_TEST

Skin punch biopsy to assess intrapidermal nerve fiber density

Also known as: Other diagnostic tests will include laser evoked potentiels, quantitative sensory testing, sudoscan, and confocal corneal microscopu

Paired healthy subjects; Patients with fibromyalgia; Patients with other chronic pain (paired for the other groups)

Eligibility Criteria

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

Study Population

Patients with fibromyalgia, other chronic pains (nociplastic or nociceptive) and healthy subjects

You may qualify if:

• patients over 18 years of age with no age limit -
• having given their signed consent to take part in the study
• affiliated to the French social security system
• able to be followed for the entire duration of the study
• reading and understanding French
• accepting the principle of the study and able to comply with its conditions
• suffering from chronic pain for at least six months of at least moderate intensity (≥ 4/10)
• fibromyalgia detected by the FiRST questionnare and defined by the revised diagnostic criteria of the WHO or chronic nociceptive or nociplastic pain without associated fibromyalgia.
• chronic pain for at least 6 months of at least moderate intensity (≥ 4/10)

You may not qualify if:

• litigation or compensation-seeking
• cancer for less than 2 years
• known cause of small-fiber neuropathy such as diabetes, systemic disease, hypothyroidism, alcohol, renal failure, genetic disease
• clinical or EMG neuropathy
• peripheral or central nervous system pathology with or without associated neuropathic pain
• uncontrolled chronic pathology such as : morbid obesity, sleep apnea, uncontrolled hypertension, etc. - psychosis, previous suicide attempt
• drug or psychoactive substance abuse
• cognitive or psychological disorders incompatible with compliance with and/or understanding of the protocol
• participation in another biomedical research protocol.

Sponsors & Collaborators

• Hospital Ambroise Paré Paris: lead

Study Sites (2)

Inserm U987

Boulogne-Billancourt, 92100, France

RECRUITING

Centre d'Evaluation et de Traitement de la douleur

Paris, 75014, France

RECRUITING

Study Officials

• Nadine ATTAL, MD PhD

  APHP

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Nadine ATTAL, MD PhD

CONTACT

0033149095931; nadine.attal@aphp.fr

Didier BOUHASSIRA, MD PhD

CONTACT

0033149094556; didier.bouhassira@inserm.fr

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Coordinator

Study Record Dates

• First Submitted: July 24, 2024
• First Posted: July 30, 2024
• Study Start: January 4, 2022
• Primary Completion: December 1, 2025
• Study Completion: May 1, 2026
• Last Updated: September 10, 2025

Record last verified: 2025-09

Locations

FR (2)