[Circadian rhythm of the pituitary-adrenal system in rheumatoid arthritis].

Two hundred and fifty-five patients with rheumatoid arthritis (RA) were examined for the levels of free cortisol and corticotrophin as well as for their circadian rhythms. It was established that the lowering of the daily average cortisol level and corticotrophin elevation in the blood as well as the desynchronization types of circadian rhythms depended on the RA gravity and the disease clinical variety. The most pronounced decrease in the cortisol level and destabilization of pituitary-adrenal function were found in the visceral RA pattern, particularly in subjects treated with corticosteroids and in those with hormone-dependent RA. Triamcinolon gave rise to a more substantial lowering of free cortisol as compared to prednisolone. It is assumed that impairment of the synchronization role of hypothalamic formations is of importance in the genesis of neuroendocrine dysfunction in RA patients.