In order to understand the disturbances in the neurophysiological, endocrine (including the hypothalamic-pituitary-adrenal axis), and immune systems objectively and in detail, we measured and compared various test items in the peripheral blood which were considered to reflect the state of these systems, in patients with rheumatoid arthritis and in control subjects.
The levels of beta-endorphin, methionine-enkephalin, epinephrin, norepinephrin (NE), dopamine, corticotropin releasing factor (CRF), adrenocoricotropic hormone (ACTH), cortisol, CD4/CD8 ratio, CD57, NK cell activity and IL-6 in the peripheral blood, which are considered to reflect the activity of this neuroendocrine-immune network, were measured and compared between 49 patients with rheumatoid arthritis (RA) and 54 healthy control subjects. The face scale (to measure mood) and the Cornell medical index (CMI) health questionnaire were administered to both groups, and pain scores were measured using a visual analog scale in the RA group.
The serum levels of NE, dopamine, IL-6 and CD4/CD8 ratio were higher, whereas the levels of beta-endorphine, ACTH and NK cell activity were lower in the RA subjects than in the control subjects. On the other hand, the serum levels of Met-enk, epinephrin, CRF, cortisol and CD57 were not significantly different between the two groups. In RA patients a positive correlation was observed between the face scale score and the serum cortisol level and between the pain score and the serum IL-6 level. The more severe the pain, the higher the NK cell activity and IL-6 concentrations in the peripheral blood. On the other hand, in healthy females none of the measured items in the peripheral blood were significantly correlated with the face scale results or the responses to the CMI health questionnaire.
In RA patients the hypothalamic-pituitary-adrenal (HPA) axis is altered and this condition is correlated to a deterioration in symptoms.