Objective: Acute stress in patients with rheumatoid arthritis (RA) should stimulate a strong stress response. After cryotherapy, we expected an increase of hormones of the adrenal gland and the sympathetic nervous system.
Methods: Fifty-five patients with RA were recruited for whole-body cryotherapy at 110°C and 60°C, and local cold therapy between -20°C and -30°C for 7d. We measured plasma levels of steroid hormones, neuropeptide Y (sympathetic marker), and IL-6 daily before and after cryotherapy.
Results: In both therapy groups with/without glucocorticoids (GC), hormone and IL-6 levels at baseline and 5hr after cold stress did not change during 7d of cryotherapy. In patients without GC, plasma levels of cortisol and androstenedione were highest after -110°C cold stress followed by 60°C or local cold stress. This was opposite in patients under GC therapy, in whom unexpectedly -110°C cold stress elicited the smallest responses. In patients without GC, adrenal cortisol production increased relative to other adrenal steroids, which was again opposite under GC therapy with a loss of cortisol and an increase of DHEA. Importantly, there was no sympathetic stress response in both groups. Patients without GC and 110°C cold stress demonstrated higher plasma IL-6 compared to the other treatment groups (not observed under GC), but they showed the best clinical response.
Conclusions: We detected an inadequate stress response in patients with GC. It is further shown that the sympathetic stress response was inadequate in patients with/without GC. Paradoxically, plasma levels of IL-6 increased under strong cold stress in patients without GC. These findings confirm dysfunctional stress axes in RA.