I thought that I would share this with you all.
I have had MS for six years now. Intrigued with how I was affected by temperature I began to record my well-being and the temperature daily. It didn't seem to correlate. Remembering how, back in 2004, I worked in an office with really extreme air conditioning and found that my symptoms eased considerably, I bought a hygrometer and found that the relative humidity of my environment and my wellbeing correlated better.
A year ago I was looking into humidity and became familiar with the measurement of 'dew point temperature.' It is arrived at through an equation making it an expression of both relative humidity (recorded by a hygrometer) and temperature |(recorded , of course, by a thermometer.) High humidity on a very cold day results in a low dew point, low humidity on a very hot day results in a high dew point. It is the temperature at which, given the humidity and temperature at any time, dew will appear on the ground… A search on Google made me aware of the work of Russell Johnson, a meteorologist with MS who made the connection between dew point temperature and MS symptoms some time ago. He has written a number of papers on the subject.
I found the correlation to be pretty close, between dew point temperature and my feeling of well being. I was amazed at just how close when I recorded my results over a couple of months.
I would decide how my spasticity was, from 1 - absolutely well through to 10 - immobile. In practice the results ranged from 7 - very stiff and having trouble moving at all, through to 3, where 3 was 'almost no support needed'. (I always rely on furniture and walls to lean on - outside the house I am a wheelchair user). I decided upon how well I felt before I checked the dew point, so as not to influence me. Some days I simply forgot to get this done, but it was nothing to do with me not feeling exceptionally well or bad or anything.
When I finally inputted all my figures into Microsoft Word to make a graph I was simply amazed. When the dew point was high I felt bad, when it was low I felt good - I was amazed at the consistency of it.
Here it is:

Some days are good, some are bad, I used to wonder why but now I know, it’s all the dew point temperature. I found this quite a revelation and now an air conditioner really helps me. I have to keep the dew point temperature below 10°. I told my neurologist about this but he wasn’t particularly interested. Everyone with MS should know about this! If, as I suspect, it has the same effects on everyone as it does me… It would also explain the short term effects of hyperbaric oxygen therapy…
If you are so inclined then get a good hygrometer and keep a diary for yourself and share the results here. I would suggest avoiding cheap hygrometers from Hong Kong though – I bought one and it was faulty. I ended up getting a combined hygrometer and thermometer designed to aid people rearing birds.
Dew point temperatures can be calculated here, jest input the relative humidity and the temperature:
http://www.decatur.de/javascript/dew/
I really was amazed!