Evaluating HPA and HPT Axes Hormones

Ten milliliters of peripheral venous blood was collected from each patient to measure the hormones of the hypothalamic–pituitary–adrenal (HPA) and hypothalamic–pituitary–thyroid (HPT) axes at 8:00 am, the day after enrolment, and the measurement was repeated at the end of the 16-week treatment period. The seven detected hormones were adrenocorticotrophic hormone (ACTH), cortisol (COR), thyrotropin-stimulating hormone (TSH), 3-triiodothyronine (TT3), thyroxine (TT4), free triiodothyronine (FT3), and free thyroxine (FT4). ACTH levels were measured using radioimmunoassay, and TSH levels were measured using the electrochemiluminescence double-antibody sandwich method. COR, TT3, TT4, FT3, and FT4 levels were measured by electrochemiluminescence quantitative assays. The normal ranges of the seven hormones levels is as follows: TSH: 0.27–4.2 mU/L, TT3: 1.3–3.1 nmol/L, FT3: 3.6–7.5 pmol/L, TT4: 62–164 nmol/L, FT4: 12–22 pmol/L, ACTH: 5.0–78 ng/L, COR (8:00 am): 147.3–609.3 nmol/L. Hormone levels above or below the reference range were both defined as “abnormal”. Patients were considered to have an abnormal HPA axis if they had at least one abnormal value of ACTH and COR levels, while they were considered to have an abnormal HPT axis if they had at least one abnormal value of TSH, TT3, FT3, TT4, and FT4 levels.