Charcot-Marie-Tooth Disease, Type IA, Motor Activity, Neuromuscular Diseases, Peripheral Neuropathy Hereditary, Walking, Difficulty
Conditions
Keywords
CMT1A, wearable sensor, actigraphy, physical activity, CMT-FOM, functional assessment, peripheral neuropathy
Brief summary
Charcot-Marie-Tooth disease type 1A (CMT1A) is the most common hereditary peripheral neuropathy, affecting approximately 26,000 patients in France. It presents as chronic and progressive sensorimotor deficits predominantly affecting the distal lower limbs, with onset typically in childhood. There is currently no specific pharmacological treatment; management remains symptomatic. This research will: In the long run, validated wearable sensors could improve patient follow-up, personalize rehabilitation, and support the design of clinical trials for CMT1A - including trials of the novel "Nano-Cur" treatment currently under development.
Detailed description
Peripheral neuropathies are frequent conditions affecting peripheral nerves with highly varied etiologies. Among genetic causes, Charcot-Marie-Tooth (CMT) disease is the leading hereditary neuropathy, with approximately 26,000 patients in France. The most frequent form, CMT1A, is caused by a duplication of the PMP22 gene, leading to chronic progressive sensorimotor deficits predominantly affecting the distal lower limbs, with onset in childhood and significant impact on quality of life. No specific pharmacological treatment exists for CMT1A. The CMT-FOM scale (Mandarakas et al., 2024, Neurology, 102: e207963) constitutes the reference for functional evaluation, but requires lengthy evaluation and a specialized technical platform, making it unsuitable for routine outpatient consultations. Furthermore, punctual evaluations may be biased by external factors (fatigue, mood, motivation) without faithfully reflecting the patient's daily neurological status. Non-invasive wearable physical activity sensors offer a promising alternative, enabling repeated and ecologically valid measurements directly at home and over prolonged periods. This study aims to assess whether such ambulatory sensors can evaluate functional impairments in CMT1A patients equivalently to a comprehensive CMT-FOM evaluation. The study will be conducted among CMT1A patients followed at the National Reference Centre for Rare Peripheral Neuropathies (Service de Neurologie, CHU de Limoges), in partnership with the Quantified Movement Analysis Laboratory (Laboratoire d'AQM), Service de Médecine Physique et de Réadaptation (CHU de Limoges). It represents a collaborative effort between research units NeurIT (UR20218) and HAVAE (UR20217). This project also forms part of the broader development of the "Nano-Cur" therapeutic compound (NeurIT/LABCiS collaboration), having led to a national and international patent filing and the creation of the start-up Curlim (AFM-Téléthon/AVRUL support).
Interventions
None listed
Sponsors
Study design
Eligibility
Inclusion criteria
1. Age ≥ 18 years 2. Genetically confirmed diagnosis of CMT1A (PMP22 duplication on chromosomal analysis) 3. Followed at the National Reference Centre for Rare Peripheral Neuropathies (Service de Neurologie, CHU de Limoges) and/or having undergone gait analysis at the Quantified Movement Analysis Laboratory (Laboratoire d'AQM), Service de Médecine Physique et de Réadaptation, CHU de Limoges 4. Ability to walk independently (with or without walking aids) 5. Informed consent obtained 6. Affiliated to French social security system
Exclusion criteria
1. Other associated neurological condition that could independently affect walking or motor activity 2. Inability to wear the sensor device (skin allergy, sensory intolerance) 3. Inability to comply with study procedures (cognitive impairment, no fixed domicile) 4. Participation in another interventional study during the same period 5. Pregnant or breastfeeding women 6. Patients under legal protection (guardianship or curatorship)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Pearson/Spearman r: daily step count (ActiGraph) vs. CMT-FOM total score | Day 1 (CMT-FOM) | Correlation coefficient (r : -1 to +1) between mean daily step count (steps/day) over 7 days and CMT-FOM total score obtained at Day 1 hospital visit. |
| Pearson/Spearman r: daily activity counts (ActiGraph) vs. CMT-FOM total score | Day 1 | Correlation coefficient (r : -1 to +1) between mean daily activity counts (raw accelerometry counts/day) over 7 days and CMT-FOM total score. |
| Pearson/Spearman r: daily sedentary time (ActiGraph) vs. CMT-FOM total score | Day 1 | Correlation coefficient (r : -1 to +1) between mean daily sedentary time (minutes/day) over 7 days and CMT-FOM total score. |
| Pearson/Spearman r: composite sensor score vs. CMT-FOM sub-scores | Day 1 | Correlation coefficient (r : -1 to +1) between ActiGraph-derived metrics and CMT-FOM sub-domain scores (upper limb, lower limb, balance, endurance). Reported separately per sub-score. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Intraclass Correlation Coefficient (ICC) of daily step count across 7 days | Day 7 (home monitoring) | Test-retest reliability (ICC (0 to 1), two-way mixed, absolute agreement) of daily step count measured by ActiGraph LEAP across 7 home monitoring days. |
| Coefficient of Variation (CV, %) of daily activity counts across 7 days | Day 7 (home monitoring) | Day-to-day variability expressed as CV (%) for raw accelerometry activity counts across 7 days. |
| Minimal Detectable Change (MDC) of daily step count | Day 7 (home monitoring) | MDC95 of daily step count (steps/day), calculated from SEM and ICC, representing the smallest change exceeding measurement error. |
| Pearson r: daily step count vs. CMT Neuropathy Score (CMT-NS) | Day 1 | Correlation (r : -1 to +1) between mean daily steps/day and CMT-NS total score at Day 1. |
| Pearson r: daily step count vs. 6-Minute Walk Test distance (meters) | Day 1 | Correlation (r : -1 to +1) between mean daily steps/day and 6MWT distance (meters) measured at Day 1. |
| Pearson r: daily step count vs. 10-Meter Walk Test speed (m/s) | Day 1 | Correlation (r : -1 to +1) between mean daily steps/day and 10MWT comfortable-pace speed (m/s) at Day 1. |
| Mean daily step count stratified by CMT-FOM severity quartile | Day 1 | Mean (±SD) daily step count compared across CMT-FOM severity quartiles (Q1-Q4) to characterise activity profiles by disease severity. |
| Mean daily sedentary time stratified by CMT-FOM severity quartile | Day 1 | Mean (±SD) daily sedentary time (min/day) compared across CMT-FOM severity quartiles. |
Countries
France