Snow Leopard
Hibernating
- Messages
- 5,902
- Location
- South Australia
I have always had a nagging feeling that the (mixed) findings related to the HPA axis in CFS patients was a red herring, but I didn't understand why I felt this way. It is clear much of our understanding of how this relates to disease is probably wrong.
The similar same observations have been found in other disease cohorts, particularly in Rheumatoid Arthritis patients and I found this 2005 article interesting:
"A defect in cortisol production in rheumatoid arthritis: why are we still looking?"
http://rheumatology.oxfordjournals.org/content/44/9/1097.full
If the HPA axis is in dynamic equilibrium with the immune system and a strong stress response suppresses the immune system, then the opposite effect would be that an activated immune system would suppress the HPA axis. This may explain the findings in RA, CFS patients as well as other groups.
Additionally, certain people like to suggest that most/all CFS patients are subject to chronic stress and this is somehow a maintaining factor. While some patients are living under stressful conditions (eg struggling in terms of finances, relationship issues and social isolation), this is not true of all patients and therefore cannot be used to explain the findings in many patients. The fact that patients are apparently experiencing high stress, yet not mounting a classic physiological stress response is never explained.
In fact the idea that "stress" is always bad appears to be a half-truth at best. Indeed in rat models, some stress has been shown to lead to increased resistance to the development of autoimmune conditions.
"Stress in autoimmune disease models."
http://www.ncbi.nlm.nih.gov/pubmed/16855134
The similar same observations have been found in other disease cohorts, particularly in Rheumatoid Arthritis patients and I found this 2005 article interesting:
"A defect in cortisol production in rheumatoid arthritis: why are we still looking?"
http://rheumatology.oxfordjournals.org/content/44/9/1097.full
If the HPA axis is in dynamic equilibrium with the immune system and a strong stress response suppresses the immune system, then the opposite effect would be that an activated immune system would suppress the HPA axis. This may explain the findings in RA, CFS patients as well as other groups.
Additionally, certain people like to suggest that most/all CFS patients are subject to chronic stress and this is somehow a maintaining factor. While some patients are living under stressful conditions (eg struggling in terms of finances, relationship issues and social isolation), this is not true of all patients and therefore cannot be used to explain the findings in many patients. The fact that patients are apparently experiencing high stress, yet not mounting a classic physiological stress response is never explained.
In fact the idea that "stress" is always bad appears to be a half-truth at best. Indeed in rat models, some stress has been shown to lead to increased resistance to the development of autoimmune conditions.
"Stress in autoimmune disease models."
http://www.ncbi.nlm.nih.gov/pubmed/16855134