Primary Parkinsonian Pain: Clinical Association and Phenotype (PHENOPAIN)

Among the different types of pain observed in Parkinson's disease, primary parkinsonian pain (PPP) is the most severe, the most difficult to treat, but also the least well characterized and the hardest to describe, not only by patients but also by neurologists. Consequently, PPP remains difficult to identify, even for clinicians with expertise in Parkinson's disease.

Nevertheless, patients with Parkinson's disease who experience PPP appear to exhibit certain demographic and clinical characteristics that may help distinguish them from other patients, including a poorer motor response to levodopa, a stronger association with sleep disturbances, and cognitive and behavioral features such as impulse control disorders (ICDs). PPP may therefore be associated with a specific disease phenotype supported by distinct pathophysiological mechanisms.

Recently, a disease progression model proposed the existence of a "Brain-First" subtype (characterized by disease onset in the brainstem) and a "Body-First" subtype (characterized by disease onset in the gastrointestinal system). Several clinical markers appear to distinguish these subtypes, notably the presence of REM sleep behavior disorder (RBD), which has been associated with the Body-First phenotype.

The association between PPP and RBD, as well as between PPP and the Body-First subtype, has never been investigated. We hypothesize that PPP may be associated with several clinical markers of the Body-First phenotype. Identifying such associations could facilitate the routine clinical diagnosis of PPP and, consequently, improve its management, which remains inadequate at present.

The primary objective is to assess the proportion of patients with primary parkinsonian pain according to the presence of probable RBD in Parkinson's disease.

This prospective, cross-sectional, non-interventional category 3 study (RIPH 3) will be conducted in 300 patients. Patients contacted through the France Parkinson Association and interested in participating in the study will be able to access the online questionnaire via a QR code or a web link. Completion of the questionnaire is expected to take no more than 15 minutes. This self-administered questionnaire will include collection of general data (age, sex, disease duration, initial motor symptoms, side of symptom onset predominance, and comorbidities), assessments of pain, migraine, sleep, constipation, olfaction, anxiety and depression and impulse control disorders.

Study Overview

• Status: Not yet recruiting
• Conditions: Parkinson s Disease
• Intervention / Treatment: Other: Online self-administered questionnaire

• Study Type: Observational
• Enrollment (Estimated): 300

Contacts and Locations

• Study Contact: Name: Lise Laclautre; Phone Number: +33473754963; Email: promo_interne_drci@chu-clermontferrand.fr
• Study Contact Backup: Name: Lise Laclautre; Email: promo_interne_drci@chu-clermontferrand.fr

Study Locations

• France
  • Clermont-Ferrand, France
    • CHU Clermont-Ferrand
    • Principal Investigator: Ana MARQUES
    • Contact: Lise Laclautre; Phone Number: +33473754963; Email: promo_interne_drci@chu-clermontferrand.fr
    • Contact: Lise Laclautre; Email: promo_interne_drci@chu-clermontferrand.fr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Patients will be contacted through the France Parkinson Association. If interested in the study, they will be able to access the online questionnaire hosted on the REDCap platform via a QR code or a web link.

Description

Inclusion Criteria:

• Age ≥ 18 years.
• French-speaking.
• Diagnosis of Parkinson's disease confirmed by a neurologist.

Exclusion Criteria:

• Atypical parkinsonian syndrome.
• Patients under legal protection (guardianship, curatorship, or legal safeguard measures).

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort

Intervention / Treatment

Parkinsonian patients; Patients with a diagnosis of Parkinson's disease confirmed by a neurologist

Other: Online self-administered questionnaire; Completion of the questionnaire is expected to take no more than 15 minutes. This self-administered questionnaire will include collection of general data (age, sex, disease duration, initial motor symptoms, side of symptom onset predominance, and comorbidities), assessments of pain, migraine, sleep, constipation, olfaction, anxiety and depression and impulse control disorders.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Presence of primary parkinsonian pain according to the 3PDQ questionnaire	This self-questionnaire is completed by the patient during the inclusion visit	at day 0
Probable REM sleep behavior disorder (RBD), as identified using the RBD-1Q (REM Sleep Behavior Disorder Single-Question Screen).	This self-questionnaire is completed by the patient during the inclusion visit	at day 0

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Presence of anosmia	Self-reported olfactory dysfunction	at day 0
Presence of constipation	Self-reported constipation dysfunction	at day 0
Presence of impulsive control disorders according the QUIP-Anytime During PD-Short (Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease)	This self-questionnaire is completed by the patient during the inclusion visit	at day 0
Presence of Anxiety and/or depression according the HADs (Hospital Anxiety and Depression scale)	This self-questionnaire is completed by the patient during the inclusion visit	at day 0
Prsence of RBD according the RBD SQ (RBD-Screening Questionnaire)	This self-questionnaire is completed by the patient during the inclusion visit	at day 0
Pain intensity according an EVA scale	patients will evaluate their pain with an EVA scale at inclusion visit	at day 0
Presence of comorbidities	Patients will report if they had comorbidities such as diabete or osteoarticular disorders.	at day 0
presence of migraines	patient will report if he had migraines	at day 0
Current antiparkinsonian and analgesic treatments	Patient will report his current antiparkinsonian and analgesic treatments	at day 0

Collaborators and Investigators

• Sponsor: University Hospital, Clermont-Ferrand

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): September 30, 2027
• Study Completion (Estimated): October 1, 2027

Study Registration Dates

• First Submitted: July 9, 2026
• First Submitted That Met QC Criteria: July 9, 2026
• First Posted (Actual): July 14, 2026

Study Record Updates

• Last Update Posted (Actual): July 14, 2026
• Last Update Submitted That Met QC Criteria: July 9, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: pain; Parkinson's disease; RBD
• Additional Relevant MeSH Terms: Synucleinopathies; Neurologic Manifestations; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurodegenerative Diseases; Movement Disorders; Parkinsonian Disorders; Basal Ganglia Diseases; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain; Parkinson Disease
• Other Study ID Numbers: RNI 2026 MARQUES; 2026-A01046-45 (Registry Identifier: n° IDRCB)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No