Prevalence of Orthostatic Tremor in Patients With Unsteadiness (EMG-SOT)

Prevalence of Orthostatic Tremor by Surface Electromyographic Recording in Patients Reporting Unsteadiness

Clinical presentation of orthostatic tremor (OT) may be misleading and simply perceived by a postural instability such as in several peripheral neuropathies. In addition, peripheral neuropathies represent the leading cause of pathologies associated with OT. Among patients referred for an electroneuromyogram (ENMG) for peripheral neuropathy and presenting with postural unsteadiness, OT assessment will be systematically performed. Demographic, clinical and polygraphy characteristics of these patients will be analyzed and prevalence of OT in the general population of peripheral neuropathies will be assessed.

Study Overview

• Status: Recruiting
• Conditions: Neuropathy; Orthostatic Tremor
• Intervention / Treatment: Diagnostic test: Polygraphy with surface electrodes

Detailed Description

Among patients who will be referred for ENMG and exploration of a neuropathy, orthostatic tremor will be investigated systematically.

Main objective and primary endpoint:

• To estimate the prevalence of OT with its 95% confidence interval in the population of patients defined above
• Presence of OT confirmed by surface EMG (polygraphy) in patients with standing instability referred for ENMG.

Secondary objectives and end points

• Determine the demographic, clinical, electrophysiological characteristics of patients with OT; Estimate the prevalence of peripheral neuropathy in patients with OT; Duration of symptoms; Correlation with quantitative neuropathy scores (ISS, MRC, ONLS, R-ODS)
• Age, sex, clinical parameters: symptoms reported by the patient (instability, tremor, weakness, pain, falls), duration, current medications, ISS score, MRC score, ONLS score, R-ODS score) and electrophysiological parameters (mean frequency of OT in Hertz, MUNIX score (number of motor units in the anterior tibialis, calculated by software on the ENMG machine).

• Study Type: Observational
• Enrollment (Estimated): 100

Contacts and Locations

• Study Contact: Name: Nathalie KUBIS, MD, PhD; Phone Number: +33149958108; Email: nathalie.kubis@aphp.fr
• Study Contact Backup: Name: Pierre LOZERON, MD, PhD; Phone Number: +33149958076; Email: pierre.lozeron@aphp.fr

Study Locations

• France
  • Paris, France, 75010
    • Recruiting
    • APHP Lariboisière Hospital, Clinical Physiology Department
    • Contact: Nathalie KUBIS, MD, PhD; Phone Number: +33149958108; Email: nathalie.kubis@aphp.fr
    • Contact: Pierre LOZERON, MD, PhD; Phone Number: +33149958076; Email: pierre.lozeron@aphp.fr

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

Any patient referred to the Clinical physiology Department for an ENMG (investigation of the neuropathy)

Description

Inclusion Criteria:

• Age ≥ 18 years old
• All patients complaining of instability when standing up and referred for an ENMG
• Patient informed and having expressed his non-opposition to participating in the research

Exclusion Criteria:

• Patient's refusal to participate in the study
• Impossibility to stand
• No affiliation to health insurance
• Patients under a legal protection measure or unable to express their will
• Patient under the State Medical Assistance (AME)
• Patient under 18 years old
• Pregnant women, parturients and breast-feeding mothers

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Patients with unsteadiness; Patients with unsteadiness referred for an ENMG	Diagnostic test: Polygraphy with surface electrodes; Patients referred for ENMG to the Clinical Physiology Department and complaining of postural unsteadiness will undergo a polygraphy recording using surface electrodes (Natus Medical Incorporated), performed at the end of ENMG

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Prevalence of orthostatic tremor (OT	Prevalence of OT (95% confidence interval) in patients complaining of postural instability and referred for ENMG	Day 0

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Inflammatory Neuropathy Cause and Treatment (INCAT) Sensory Sum Score (ISS) simplified	The ISS ranges from 0 (normal sensation) to 20 (most severe sensory deficit) and is composed of the summation of the following sensation evaluations : pinprick arm grade (range 0-4) ; vibration arm grade (range 0-4) ; pinprick leg grade (range 0-4); vibration leg grade (range 0-4): two-point discrimination grade (range 0-4)	Day 0
Medical Research Council (MRC) score	The MRC score grades muscle power on a scale of 0 (no detectable contraction) to 5 (normal force, comparable to the healthy side)	Day 0
Overall Neuropathy Limitations Scale (ONLS) score	The ONLS score is be completed by adding the total of the Arm disability scale score (0-5) and Leg disability scale score (0-7) yielding a total score of 0-12 (higher score indicates higher disability)	Day 0
Rasch-built Overall Disability Scale (R-ODS) score	R-ODS scale comprising 24 items evaluates the ability to perform daily activities. The answers are rated on a scale of 0 to 48 (with 0 being very poor and 48 being best performance)	Day 0
OT frequency	OT frequency in Hz	Day 0
Motor unit number index (MUNIX)	MUNIX is a method for assessment of number of motor units using the compound muscle action potential (CMAP) and surface electromyographic interference pattern (SIP).	Day 0

Collaborators and Investigators

• Sponsor: Assistance Publique - Hôpitaux de Paris
• Investigators: Principal Investigator: Nathalie KUBIS, MD, PhD, APHP, Lariboisière Hospital

Study record dates

Study Major Dates

• Study Start (Actual): April 27, 2021
• Primary Completion (Estimated): April 1, 2024
• Study Completion (Estimated): April 1, 2024

Study Registration Dates

• First Submitted: April 9, 2021
• First Submitted That Met QC Criteria: April 9, 2021
• First Posted (Actual): April 14, 2021

Study Record Updates

• Last Update Posted (Estimated): January 3, 2024
• Last Update Submitted That Met QC Criteria: January 1, 2024
• Last Verified: January 1, 2024

More Information

Terms related to this study

• Keywords: Tremor; Polygraphy; Unsteadiness; Electroneuromyography; Anti-MAG neuropathy; Chronic demyelinating inflammatory neuropathy
• Additional Relevant MeSH Terms: Nervous System Diseases; Neurologic Manifestations; Dyskinesias; Tremor
• Other Study ID Numbers: APHP191089; 2019-A02976-51 (Registry Identifier: IDRCB)

Drug and device information, study documents

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