What is heat sensitivity? Many people with MS find that their symptoms get worse in hot situations. This can be triggered by hot baths, the sun, or exercise. The effects of heat are temporary, but heat sensitivity can be extremely unpleasant. Plain and simple, I hate heat of any kind!! Ever since my diagnosis in ’91 heat has been one of my worst symptoms. That includes the sun, hot tubs, saunas, sweaters, warm clothes, hot showers and fevers from colds or flu. Humidity isn’t much fun for me, either. I can only take off so much clothing before becoming illegal. lol
When I get too hot my skin starts crawling, my eyes can blur, I feel more tired and when I could still walk, my walking would be wobbly. Not enough to topple over and fall down but I could sense something wasn’t right! Some people with MS have the same problems with cold! For many people, being cold can affect nerve and muscle activity, resulting in discomfort and mobility issues.
Since my diagnosis, I’ve never minded cold weather until November 2020. In North Dakota, the winters can be cold and brutal. Lots of cold temps and high wind chills. When it’s cold like that I just don’t go outside anymore.
Dr. Wilhelm Uhthoff, a German ophthalmologist was the first to describe Uhthoff's phenomenon (also known as Uhthoff's syndrome, Uhthoff' symptom, and Uhthoff's sign) in 1890. He noticed that people with optic neuritis, a common symptom of MS in which your optic nerve is swollen, had a temporary worsening of their vision when they exercised. For people that suffer from Uhtoff’s, it can involve a worsening of their symptoms or triggering a full-blown MS exacerbation. The reason is that heat impairs the ability of demyelinated nerves to conduct electrical impulses.
One of my first noticeable MS symptoms happened when I was managing a health club in Northfield, MN. I would play racquetball with somebody. Every time I played my eyes would get cloudy or blurry for the first 10 minutes I was on the court. This seemed very strange to me. I was concerned but after 10 minutes my eyes would always clear up, so I didn’t panic.
My cloudy eyes weren’t just in Northfield, either. Wherever I played racquetball my eyes would cloud up. I thought it had something to do with the bright lights on the courts. In hindsight, I would always stretch and loosen up in saunas before playing. I was having what Dr. Uhthoff had discovered in 1890! The optic nerves in my eyes were being affected by the heat in the saunas.
Initially, both Uhthoff and other specialists believed that the exertion involved in exercising was the cause of this phenomenon. Researchers later discovered that the real culprit was the resulting increase in body temperature, not exercise itself. This observation led to the hot bath test. Doctors used this to help diagnose people with MS before the advent of modern imaging tests. Exactly as it sounds, the hot bath test involved placing a patient suspected of having MS in a hot bath to see if his or her symptoms worsened with the heat.
The hot bath test sounds kind of barbaric these days. However, when I think back to how I use to feel after sitting in a hot whirlpool I know what Uhthoff was talking about. My symptoms would worsen. However, at the time I didn’t know they were symptoms of something bigger.
Scooterjon
