Is repetitive transcranial magnetic stimulation effective in reducing endometriosis-associated pain? A pilot randomized control trial (RCT)
Endometriosis is an inflammatory chronic pain condition caused by uterine tissue growing outside of the uterus. Although this condition affects about 1 in 9 women, current knowledge about it is very limited. The substantial gap in knowledge about endometriosis prevents affected people from receiving effective and necessary treatment.
The goal of this study is to investigate whether a non-invasive brain stimulation technique also known as repetitive transcranial magnetic stimulation (rTMS) can help reduce pelvic pain in women who still experience pain after surgery for endometriosis. Post-operative recalcitrant endometriosis-associated pain (EAP) is a common experience for many women. This type of pain, which healthcare providers struggle to fully comprehend, can have significant effects on mental health and overall well-being. Unfortunately, the current treatment for EAP falls short, as nearly half of the patients continue to suffer from inadequately managed pain for extended periods of time. It’s probable that these ongoing pains happen because the body’s way of dealing with pain has changed. rTMS changes how the brain cells work when dealing with pain, and it has shown some positive results in reducing other types of long-lasting pain.
We are aiming to recruit 60 participants with endometriosis-associated pain for this study. The study intervention period will last up to 2 weeks, depending on which treatment a participant is assigned to, with a follow-up period lasting 1 week. The 60 participants will be randomized to receive active or sham rTMS, and a standard (5 session) or extended (10 session) protocol.
Participation begins with a telephone discussion and screening session to assess eligibility and to review the study as a whole to determine eligibility and ability to participate.
Those that are eligible and keen to participate in the study will be sent a series of seven online questionnaires, to understand physical and emotional factors that may contribute to the effectiveness of the rTMS treatment for pain reduction, over a period of up to five days. The questionnaires collect information about endometriosis symptoms, pain experienced regularly that is associated with endometriosis, other body pain and recurrent symptoms such as headaches, bowel and bladder issues, stress, anxiety, mood and attitudes towards pain.
Following the completion of the questionnaires, participants will be scheduled to attend an assessment in our research laboratory. The laboratory session involves an evaluation of pain sensitivity and an evaluation of pain sensitivity over time.
Once the in-lab session has been completed the participant will be randomized into 1 of the 4 treatment groups and will be guided and followed through the study intervention, which will be 5-10 sessions of rTMS occurring within a 2 week period.
Within the week following completion of the study intervention sessions, the participant will repeat the online questionnaires as well as a Global Perception of Pain Improvement as well as their satisfaction with the study intervention. The participant will attend a second in-lab session, as was completed before the study intervention.
At 4 weeks and again at 12 weeks after the study intervention sessions are complete, the participant will repeat the online questionnaires completed immediately after the intervention sessions.
This will conclude the study.
- Women 18+ years old and have not yet reached perimenopause
- Reports of recalcitrant endometriosis-associated pain post-operatively
- No contra-indications to rTMS:
- metal/implants around the head/neck,
- Electronic implants: i.e. cochlear implants, pacemaker,
- history of epilepsy (history of seizures) in the family
- neurological conditions: stroke, multiple sclerosis, spinal cord injury
*further eligibility criteria assessed in the telephone screening process