Activity of the neuroendocrine axes in patients with polymyalgia rheumatica before and after TNF-α blocking etanercept treatment.
BACKGROUND
In this study, we evaluated the activity of the neuroendocrine axes in patients with polymyalgia rheumatica (PMR) before and after tumor necrosis factor (TNF)-α-blocking etanercept treatment, which previously has been shown to reduce interleukin 6 (IL-6) and C-reactive protein (CRP) markedly in PMR.


METHODS
Plasma samples were collected from 10 glucocorticoid-naïve patients with PMR and 10 matched controls before and after etanercept treatment (25 mg biweekly for 2 weeks). The primary end points were pre- and posttreatment levels of adrenocorticotropic hormone (ACTH), cortisol, adrenaline, thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH), prolactin, and insulin-like growth factor 1 (IGF-1).


RESULTS
Before TNF-α-blocking treatment, plasma TNF-α, ACTH, and cortisol levels were higher in patients versus controls (P < 0.05 and P < 0.001, respectively); during TNF-α blockade in patients, levels of both hormones decreased (P < 0.05 and P < 0.01, respectively), whereas levels in controls increased (P < 0.05), abolishing the pretreatment differences. Pretreatment adrenaline levels were more than twice as high in patients than in controls (P < 0.01); after treatment in patients, levels had decreased (P < 0.05) but remained higher versus controls (P < 0.05). Levels of the other hormones never differed significantly between groups (P > 0.05).


CONCLUSIONS
In PMR, TNF-α may increase the activities of the hypothalamic-pituitary-adrenal and the hypothalamic-sympthoadrenomedullary axes. Secretion of TSH, FSH, prolactin, and IGF-1 is not clearly changed in PMR.


BACKGROUND
ClinicalTrials.gov (NCT00524381).
Frederik Flindt
FF
Kreiner
Henrik
H
Galbo
D000368:Aged; D018501:Antirheumatic Agents / Q000494:pharmacology / Q000627:therapeutic use; D000068800:Etanercept; D005260:Female; D006801:Humans; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects / Q000378:metabolism*; D007074:Immunoglobulin G / Q000494:pharmacology / Q000627:therapeutic use*; D008297:Male; D009490:Neurosecretory Systems / Q000187:drug effects; D010913:Pituitary-Adrenal System / Q000187:drug effects / Q000378:metabolism*; D011111:Polymyalgia Rheumatica / Q000097:blood* / Q000175:diagnosis / Q000188:drug therapy*; D018124:Receptors, Tumor Necrosis Factor / Q000627:therapeutic use*; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors*
D018501:Antirheumatic Agents; D007074:Immunoglobulin G; D018124:Receptors, Tumor Necrosis Factor; D014409:Tumor Necrosis Factor-alpha; D000068800:Etanercept