Friday, June 19, 2009

What Causes the Fatigue of Rheumatoid Arthritis?

What Causes RA Fatigue?

The fatigue of Rheumatoid Arthritis is a weariness that rest cannot cure. It is tiredness without the benefit of the pleasure of activity. Over 90% of RA patients report fatigue as a clinical symptom. It is counted second only to pain as the greatest difficulty of living with RA.

Where does this weariness come from? What causes us to feel precisely like Superman with Kryptonite pushed in his face? Does anybody know?

Likely, there are multiple contributing factors. Most suspicious-sounding to me are the Cytokines. These are chemicals which some scientists believe cause the fatigue of colds and flu. They are the chemical messengers of the immune system. There are over 150 different kinds of these protein-based molecules.

These chemicals are used by cells as a means of communication. Cells can talk to each other through Cytokines, but in Rheumatoid Arthritis, excess amounts of them are produced and dumped off into the bloodstream. Some theorize that they cause several RA symptoms, including fatigue, anemia, sleep problems, and skeletal muscle shrinkage. (See conquering Rheumatoid Arthritis by Thomas Lee, Ph.D., p.47).

One reason that I’d be willing to blame the Cytokines is that they are reduced by TNF blocking medications (like Enbrel). And guess what results? Yes, usually fatigue is lessened. This is one of the reasons that fatigue is said by some to mirror disease activity or reflect inflammation levels: when medications slow inflammation, fatigue tends to moderate.

The fatigue of Rheumatoid Arthritis is not caused by exertion. However, activity can aggravate it. It sounds like “heads I win; tails you lose.” Rest is critical to surviving life with Rheumatoid Arthritis, but it will not prevent the fatigue.

Funny thing: I have read as many times that depression causes the fatigue as I have read that fatigue causes depression. This is not a fair fight. We have to fight the fatigue while we are in a state of chemically-induced tiredness. And we must fight back depression from an exhausted state. And how could we be anything BUT fatigued when managing such extreme pain levels over an extended time?

Other legitimate theories for explaining the fatigue of RA include anemia and nutritional deficiencies. Red blood cells can be reduced by both the disease and some of its treatments. Similarly, both Rheumatoid Arthritis and many of the medicines prescribed for it tend to curb normal appetite.

I read some abstracts and medical journals to see if anything new is being uncovered about the fatigue of RA. One experiment was done with mice to show how inflammation impacts the brain. Immune cells infiltrate the brain which, according to one reporter, causes the proverbial brain fog.

I don’t know how the mice are coping, but I’m sure hoping for answers – because I am tired being tired. How did Superman ever solve that Kryptonite problem, by the way? It was blue Kryptonite.


Synovial Sensation said...

I'd love to wash those moncytes right out of my hair! Thanks for this. Going for a little lie down now :)

Kelly Young said...

So glad you stopped by, Synovial!
That is my kind of funny!

Kelly Young said...

instead of Selsun blue,
we could sell Krytonite blue shampoo.

andrew said...

That must be why my rhuemy was very happy when I told him that my energy level was back up since taking Enbrel.

Kelly Young said...

Glad to hear the good report.
I'm think mine has me up to second gear agsin, too. :)

Unknown said...

Thanks for writing about fatigue. I don't think anyone without ailments that cause such awful exhaustion understands it. I have had friends on chemo that suffer from fatigue and they say no one can understand that either.

I also want to thank-you for explaining all this in easy to understand terms. What is your background, education? MD, medical degree? Whatever, you sure are excellent in research and writing.

Kelly Young said...


Thank you Dazey. Your RA Warrior is a humble teacher. And a really hard worker. ;D