"Is heat intolerance also a post-polio problem? …"


by Richard Bruno PhD This article is from the Polio Post News North Central Florida Post-Polio Support Group Sept 03



I read about ‘cold intolerance’, that Polio Survivors are always cold.  My feet are always cold in the winter, but I have the most trouble in summer.  I get exhausted in the heat, especially when it’s humid.  Is heat intolerance also a post-polio problem?


Dr Bruno’s Answer:

You bet. In our 1985 National Post-Polio Survey cold caused muscle weakness in 62% of polio survivors, muscle pain in 60% and fatigue in 39%. But that survey also found that 39% of Polio Survivors have fatigue when it’s hot.


Whether it is cold or hot, polio survivors have three strikes against them when it comes to controlling their body temperatures.  First, the poliovirus damaged the hypothalamus, the part of the brain that serves as the body’s thermostat.  Second, the polio virus killed neurons in the spinal cord that make the veins in your skin become smaller or larger as the temperature changes. 


Basically, polio survivors’ veins are always too big.  When its cold outside warm blood pools in those big veins near the surface of the skin, causing heat in the blood to radiate into the air, the skin to get very cold and to look purple or even blue.  When it’s hot outside, or when polio survivors take a long hot bath or shower, the skin becomes lobster red as the veins and the arteries open wide and hot blood rushes to the skin.


When polio survivors stand up, gravity pulls blood into the open veins in their legs and blood pressure can drop, causing fatigue, light headedness or even a faint.  And then there’s the third strike:  Polio survivors who have smaller leg muscles due to polio damage causing muscle atrophy, have more blood pooling in the lower legs, since muscle contraction is needed to help to pump blood back toward the heart.


So, since your body now can’t regulate its own temperature, you will have to do it.  Our 1983 study found that polio survivors’ nerves function as if it is 20 degrees colder than the temperature of their skin.  So in winter, polio survivors should dress as if it is 20 degrees colder than the outside temperature.  You need to dress in layers so that you can regulate your body temperature by changing the amount of insulating clothing covering your body.


But the trick is to stay warm from the word go.  You should dress straight after showering when your skin is warm and red.  Try wearing heat-retaining socks or even long-johns.  (If you ever need surgery remember to remind the doctors and nurses that you get cold easily so they can provide a heated blanket in the recovery room.)


When it is hot, stay out of the sun, move more slowly and take more frequent rest breaks with your feet elevated to make it easier for blood to flow back to your heart so that you can prevent foot swelling and keep your blood pressure up.  It’s especially important to have smaller amounts of food for lunch, have cool foods and cold drinks, and to take a feet-up break after eating, since midday is when polio survivors have the most trouble with dropping blood pressure and fatigue 


It’s also a good idea to take cooler baths or showers in summer and to keep the air conditioning turned up.  Cool the car down too before getting in during the summer.  But be careful. Whether you’re being chilled by winter winds or by air-conditioning in summer, always cover your upper body, especially your neck, to prevent muscle spasms and headaches caused by cold air blowing on your muscles.


Many polio survivors don’t realise that they can have as many symptoms and sometimes even more, during the change of seasons, when the thermometer goes up and down from day to night and from day to day.  Autumn and spring bring increases in symptoms, especially muscle pain and headaches, as polio survivors’ temperature-challenged bodies can’t decide if they should sweat to stay cool or shiver to stay warm.  Layering of clothing is especially important in a thermally-confused world for the bodies of polio survivors, unable to adapt to the temperature.


Tessa’s Comments:

With summer approaching, excessive sweating in the heat can lower our potassium levels making it more difficult to cope with the heat of summer.  Heat drains us of energy when potassium is low and palpitations and heart problems can occur.  Low potassium also increases muscle weakness and swelling.  As you need a doctor’s prescription to get Slow K now, an alternative is boiling potato skins and drinking the water (make it into soup) to get more potassium.  (Never throw your vegetable water away – full of minerals.)  Other good food sources include most nuts, sunflower seeds, carrots, apricots, avocados and of course bananas.