Efficacy of Home-delivered Transcranial Direct Electrical Stimulation or Chronic Pain

Official title

Efficacy of Home-delivered Transcranial Direct Current Stimulation (tDCS) of the Motor Cortex in Patients With Chronic Pain Transiently Relieved by Motor Cortex rTMS : a Pragmatic Randomized Double Blind Sham Controlled Trial

Overview

This clinical investigation aims to evaluate the efficacy and safety of a home-based device providing electrical stimulation of the brain named transcranial direct current stimulation (tDCS ) , in patients with chronic pain who have been transiently relieved by repetitive transcranial magnetic stimulation delivered at hospital (less than one month benefit). The general objective is to show that these patients may best benefit from home based tDCS while rTMS performed in hospital has only limited and transient efficacy. Each participant will be randomized into one of two arms to receive during 3 months either active tDCS or sham tDCS. Neither the investigator nor the patient will be aware of the treatment. The efficacy will be assessed on pain intensity (primary outcome at 3 months) and several secondary outcomes (qualify of life, pain symptoms , global impression of change, pain relief, sleep, anxiety, depression) every month for up to 3 months. Safety will be assessed at each follow up visit for up to 3 months. The participants will be asked to self stimulate themselves with the device 5 days per week for about 20 minutes.

Detailed description

This will be a randomised, double-blind, parallel-group, bi-centric study versus placebo stimulation. Patients undergoing previous treatment with rTMS of the motor cortex in routine in our pain center and with at least 30 % pain relief with rTMS (after 10 sessions) but only transient pain relief (less than one month) will stop their treatment for at least one month. They will then be randomised to receive one of the 2 treatments under study (active tDCS of the motor cortex, placebo tDCS of the motor cortex, TENS eco plus). The protocol will involve a 20-minute tDCS session (2 mA) at home, 5 days a week for 12 weeks. The treatment will continue for 12 weeks and the final evaluation will take place at 12 weeks.

TENS ECO PLUS is a portable transcranial direct current stimulation (tDCS) system (tDCS kit) supplied by the Monath Electronic laboratory, designed for use at home; this system will first be tested in hospital during a test session with explanations to the patient on how to use it. The stimulation intensity is blocked above a certain threshold by the system to avoid any risk of epileptic seizure. Sham or placebo stimulation uses the same medical device without active stimulation.

Given the exploratory nature of the trial and in order to reduce study participant's exposure to a potentially useless treatment, blinded interim analysis will be conducted dring the course of the trial in the first 40 enrolled patients and the study will be stopped early if this analysis suggests large differences between the two treatment groups or conversely shows obvious futility.

Interventions

• Device tDCS of the motor cortex
  Home-delivered tDCS device

Primary outcome measures

• Self reported pain intensity in a diary [Time frame: Baseline and 12 weeks]

Secondary outcome measures (12)

• Effects on self reported pain intensity over the course of the study [Time frame: over the course of the study from baseline to week 12]
• EQ-5D-5L (EuroQol) [Time frame: Baseline, then week 1 (± 3 days), week 4, week 8 and week 12]
• Brief Pain Inventory [Time frame: Baseline, then week 1 (± 3 days), week 4, week 8 and week 12]
• Neuropathic Pain Symptom Inventory (NPSI) [Time frame: Baseline, then week 1, week 4, week 8 and week 12 after the treatment]
• Fibromyalgia Impact Questionnaire (FIQ) [Time frame: Baseline, then week 1 (± 3 days), week 4, week 8 and week 12]
• Hospital anxiety and depression scale (HADS) [Time frame: Baseline, then week 1 (± 3 days), week 4, week 8 and week 12]
• Medical outcomes study sleep scale (MOS sleep) [Time frame: Baseline, then week 1 (± 3 days), week 4, week 8 and week 12]
• McGill pain questionnaire short form (SF-MPQ) [Time frame: Baseline, then week 1 (± 3 days), week 4, week 8 and week 12]
• Pain Catastrophizing Scale (PCS) [Time frame: Baseline then 1 week ± 3 days then 4 weeks, 8 weeks and 12 weeks]
• Patient global impression of change (PGIC) [Time frame: Baseline then 4 weeks, 8 weeks and 12 weeks]
• Treatment-emergent adverse effects of home delivered tDCS [Time frame: Every day over the course of the study and at each follow up visit, at days 3 (initial follow up safety visit) then days 10, week 4, week 8 and week 12]
• Categorical pain scale [Time frame: Baseline then 10 days (± 3 days), 4, 8 and 12 weeks]

Eligibility criteria

Inclusion criteria

Chronic pain for at least 6 months Pain intensity ≥ 4/10 on 0-10 NRS Pain present every day or nearly every day Neuropathic pain (DN4 score ≥ 4/10) or nociplastic pain (Kosek et al Pain 2021) Patients previously treated with rTMS of the motor cortex in routine in our pain center but with only transient efficacy (ie, efficacy for less than one month, defined as pain intensity improved by at least 30 %) Affilitated to social security

Exclusion criteria

Contraindications to tDCS as stated in the manufacturer brochure (ie, implantable device , severe cognitive disorders, epilepsia, skin problems where will placed the electrodes, arterial or venous thrombosis, thrombophlebitis, metallic intracranial implant, cranioth-omy, incracranial aneuvrysm, cerebral tumor, severel sleep disorders such as narcolepsia) Conciomitant treatment which might increase the risk of epilepsia such as high doses opioids (≥ 140 mg morphine equivalent) or high. doses tricyclic antidepressants (≥ 150 mg per day) Pregnancy or lactation Age below 18 or > 80 years Pending litigation related to pain Pain more severe than neuropathic or nociplastic pain requiring treatment Severe disease such as cancer Severe psychiatric condition (psychosis) Impossible to be followed for up to 3 months Participation in a recent protocol (less than 3 months) Psychoactive drug abuse

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Double blind

Primary purpose

Treatment

Study locations

France · 1 center

• Centre d'Evaluation et de Traitement de la douleur, INSERM U 987 — Boulogne-Billancourt

Identifiers

NCT: NCT07211256 · 2023-A02797-38

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗