Distinct and combined effects of core and skin temperature increases on heat-related symptoms in individuals with Multiple Sclerosis

Studies

Study Title: Distinct and combined effects of core and skin temperature increases on heat-related symptoms in individuals with Multiple Sclerosis
Rationale: Even a small rise in body temperature can temporarily make neurological symptoms worse in people living with multiple sclerosis (MS). These symptoms may include tiredness, muscle cramps or weakness, blurred or double vision, numbness or tingling, balance problems, and trouble thinking clearly. We still don’t know exactly why this happens. This study will look at how changes in core (inside) and skin temperature affect these symptoms. Understanding what causes heat sensitivity can help us find better ways to manage it. If symptoms get worse because of higher core temperature, cooling the internal body temperature, like drinking cold water, may help. If it is due to higher skin temperature, using things like cooling clothes might be better.
Study Description: The goal of this study is to better understand why people living with MS are sensitive to heat. Specifically, we are looking at how your internal body temperature (core temperature) and skin temperature may affect heat-related symptoms, such as fatigue, muscle weakness, blurred or double vision, poor coordination, and confusion. Understanding why people living with MS experience this heat-related response could help us develop more targeted management strategies, such as cooling strategies and individualized exercise programs, to help maintain their independence, functional capacity, and overall quality of life.

To do this, we will use a whole-body suit that looks similar to a diving suit. The suit has small tubes that allow us to circulate warm or cool water around your body, which helps us safely change your body temperature.

During the study, you will wear the suit and sit in a comfortable dental chair. We will first gently heat your body and then cool you down. During the protocol, you will complete a few simple tests, including handgrip strength, hand coordination, memory, and attention. We will also monitor your heart rate, blood pressure, core and skin temperature, fatigue, and comfort throughout the study.

We will measure your core temperature using an ingestible gastrointestinal (GI) temperature sensor/pill, which is similar in size and appearance to a vitamin. Before using the pill, you will need to complete a screening form to make sure it is safe for you to take it.
To be eligible for the study, you should:
  1. Have relapsing-remitting MS (RRMS)
  2. Have experienced heat sensitivity at least once
  3. Be at least 3 months past your most recent relapse
  4. Have an Expanded Disability Status Scale (EDSS) score between 0 and 6

Before participating, you will meet with the neurologist on our research team, Dr. Suresh Menon, Director of the MS Clinic at Hamilton General Hospital. He will complete the medical screening with you and determine your EDSS score. You can only participate in the study after receiving his approval.

The study will take place at the Environmental Ergonomics Laboratory (Welch Hall 17) at Brock University in St. Catharines, ON.

Study Procedures:
  1. In-person or virtual meeting with Principal Investigator (Georgia Charachousou): We will go through the screening and consent forms together to determine whether you are generally eligible to participate. This will also be an opportunity to answer any questions you may have about the study.
  2. Meeting with Dr. Suresh Menon: He will complete the medical screening and EDSS assessment with you and review the MS symptoms checklist (symptoms you may experience during heat sensitivity episodes) and the GI temperature pill screening form (eligibility criteria for using the temperature pill) in more detail.
  3. Familiarization session (approximately 1 hour; $10 compensation): You will come to our lab at Brock University, where I will explain the study protocol in detail and answer any questions you may have. You will also become familiar with the scales and tests that you will complete during the experimental session.
  4. Experimental session (approximately 4 hours; $40 compensation): This is the main study session, where you will complete the experimental protocol.

Please reach out if you are interested or have any questions about the study.
Recruitment Dates: 2026-08-27 to 2027-08-27
Who can participate: You may take part in this study if:

  • You have been diagnosed with relapsing-remitting MS for at least two years and have experienced heat sensitivity symptoms (e.g., increased fatigue, muscle weakness, blurred or double vision, numbness or tingling, balance issues, trouble concentrating or slower thinking) at least once in your life.
  • You are classified from 0-6 at the expanded disability status scale (EDSS). You can calculate your score together with Dr. Suresh Menon, neurologist and MS specialist.
  • You are at least three months past your most recent relapse.
  • You have not used nicotine products (including cigarettes, vapes/e-cigarettes) or cannabis in any form in the past 12 months.
  • You consume no more than 2 alcoholic drinks per week.
  • You have no history of metabolic, pulmonary, or cardiovascular disease. You may take part in this study even if you are taking medications. Please make sure to see the screening form for examples and list all the medications that you are taking to the screening physician so that they can help you decide if it is safe for you to be in the study.

You cannot participate in this research if:

  • You cannot use the GI temperature pill
  • You have ataxia (difficulty controlling movement) in the upper limbs
  • You have a history of head injury (concussion in the past year) or any other medical condition affecting cognition, seizures, and other neurological disease.

This study is only available in English.
Trial Institution: Brock University
Trial Investigator: Georgia Charachousou, PhD (c), CSEP-CEP
Contact Information: zz24ex@brocku.ca
Trial Funding: NSERC Discovery Grants Program