To assess hypothalamic-pituitary-adrenocortical axis function in patients with rheumatoid arthritis (RA) not previously treated with glucocorticoids in relation to their inflammatory condition and in comparison to healthy controls.
We evaluated, in 10 premenopausal patients with RA and 7 age matched controls, plasma dehydroepiandrosterone (DHEA), its sulfate (DHEAS), and cortisol concentrations, together with inflammatory cytokine levels [interleukin 6 (IL-6) and IL-12], both in basal conditions and after stimulation with ovine corticotropin releasing hormone (oCRH) and with low dose intravenous (5 microg) adrenocorticotropic hormone (ACTH).
DHEA and DHEAS basal concentrations were found to be significantly lower (p<0.05) in premenopausal patients with RA than in controls. As expected, significantly higher basal levels of IL-6 and IL-12 (p<0.05) were found in patients with RA. After the low dose ACTH testing, the DHEA area under the curve value was found to be significantly lower (p<0.01) in patients than controls. Similar results, but without statistical significance, were observed after oCRH stimulation. DHEA levels at basal time showed a significant negative correlation with the erythrocyte sedimentation rate and platelet count, as well as with the Steinbrocker class of the disease (p<0.05). Normal plasma cortisol levels during oCRH and ACTH testing were found in patients with RA in spite of their inflammatory condition. After ACTH testing, IL-6 levels decreased significantly (p<0.05), whereas IL-12 levels were unchanged. No significant changes in IL-6 and IL-12 levels were found after oCRH testing.
The abnormal androgen concentrations observed during testing in patients with RA might support the implication of adrenal androgens in the immune/inflammatory cytokine mediated mechanisms involved in the pathophysiology and clinical aspects of RA.