What are non-MS causes of fatigue?
There are many other causes, including neuroendocrine and hypothalamic causes, motor system fatigue, and problems with the immune system. In terms of the motor causes, impaired drive from the motor cortex, decreased motor unit firing, inadequate motor unit recruitment, as well as impaired muscle metabolism all are important. In terms of the immune factors, we know that in MS (as well as in other diseases) when we use medications that are cytokines (like the interferons), many people report they have transient fatigue (or short-lived fatigue). Animal studies have shown that different cytokines when administered to animals can cause fatigue. There has been a range of different reasons to think cytokines are important in fatigue because other autoimmune diseases that are based on immune dysfunction also have fatigue as a component. In terms of axonal injury, we know that atrophy, low NAA, changes in the normal-appearing white matter, all contribute. Among the neuroendocrine reasons for fa
