Objectives: To evaluate function of the hypothalamic-pituitary-adrenal (HPA) axis, adrenomedullary hormonal system (AMHS), and sympathetic noradrenergic system (SNS) in premenopausal women with systemic sclerosis (SSc).
Methods: Insulin-induced hypoglycemia (0.1 IU/kg) was performed in 17 longterm, glucocorticoid-naive SSc patients with low disease activity and in 18 healthy women matched for age and body mass index (BMI). Concentrations of glucose, adrenocorticotrophic hormone (ACTH), cortisol, androstenedione (ASD), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate (DHEAS), 17a-hydroxyprogesterone (17OHP), epinephrine (EPI), norepinephrine (NE), interleukin 1ss (IL-1ss), IL-6, and tumor necrosis factor-a (TNF-a) were analyzed in plasma.
Results: Basal plasma levels of cortisol, ASD, 17OHP, DHEAS, IL-1ss, IL-6, and TNF-a were not significantly different in SSc compared to controls. Patients had higher basal ACTH (6.76 +/- 1.0 pmol/l in SSc vs 4.14 +/- 0.45 pmol/l in controls; p < 0.05), lower basal DHEA (9.02 +/- 1.64 nmol/l in SSc vs 17.0 +/- 2.8 nmol/l in controls; p < 0.05), and lower basal NE (1.61 +/- 0.26 nmol/l in SSc vs 2.57 +/- 0.38 nmol/l in controls; p < 0.05). Patients had comparable responses of glucose and ACTH to hypoglycemia. General linear model for repeated measurements, with BMI and age as covariates, revealed that the responses of 17OHP (p < 0.05), ASD (p < 0.05), DHEA (p < 0.01), EPI (p < 0.001), and NE (p < 0.001) to hypoglycemia were lower in SSc compared to controls. Cortisol response to hypoglycemia tended to be lower in SSc patients (p = 0.06) compared to controls.
Conclusion: Our data indicate decreased adrenocortical and adrenomedullary functions in premenopausal women with SSc. Whether the observed changes in the neuroendocrine system are secondary to chronic disease deserves further investigation.