Determination of cortisol cut-off limits and steroid dynamics in the ACTH stimulation test: a comparative analysis using Roche Elecsys Cortisol II immunoassay and LC-MS/MS.

PURPOSE: Measurement of cortisol concentrations is method dependent. The study aimed to establish assay-specific cut-off limits for cortisol after adrenocorticotropic hormone (ACTH) stimulation, comparing Roche Elecsys Cortisol II immunoassay to liquid chromatography-mass spectrometry (LC-MS/MS), and to assess the impact of patient characteristics, estrogen containing oral contraceptives as well as relation to other adrenocortical steroid hormone dynamics. METHODS: One hundred healthy participants underwent a 250 µg ACTH-test, with plasma samples analyzed using ElecsysCortI, ElecsysCortII, and LC-MS/MS. Cortisone, corticosterone, 17-OH-progesterone, dehydroepiandrosterone sulfate (DHEAS), androstenedione, and testosterone were additionally analyzed with LC-MS/MS. Cut-off limit for a normal cortisol response to the ACTH-test was defined as: 2.5th percentile-1.96 × SE. RESULTS: ElecsysCort II measured cortisol concentrations 21% (95% CI: 19-22%) lower than ElecsysCort I. Cut-off limits for cortisol 30 and 60 min after ACTH were 426 and 485 nmol/L (ElecsysCort II) and 411 and 470 nmol/L (LC-MS/MS). Cut-offs were unaffected by gender, or body-composition. The ACTH-test resulted in significantly increased adrenocortical steroid hormones, except for decreased cortisone concentrations (both sexes), and decreased testosterone in men (1.9 nmol/L, 95% CI: 1.3-2.5). Testosterone was increased in women (0.07 nmol/L, 95% CI: 0.02-0.13). CONCLUSION: ElecsysCort II has high analytical performance and yields significantly lower cortisol concentrations than prior polyclonal immunoassays. This clinically relevant difference underscores the necessity for revised cut-off limits for improved diagnostic precision. Suggested 30-minute cortisol cutoff limits are 411 nmol/L (LC-MS/MS) and 426 nmol/L (ElecsysCort II). Adrenocortical steroids increased upon ACTH stimulation, except for cortisone in both sexes and testosterone in men, both of which decreased.

Dual-release hydrocortisone improves body composition and the glucometabolic profile in patients with secondary adrenal insufficiency.

PURPOSE: Studies have suggested improved metabolic profiles in patients with adrenal insufficiency treated with dual-release hydrocortisone (DR-HC) compared with conventional hydrocortisone (C-HC). This study investigates the effect of DR-HC compared with C-HC treatment on five health variables: diurnal salivary cortisol/cortisone, body composition, bone health, glucose metabolism, lipids, and blood pressure. METHODS: Prospective study of 27 participants (24 men) with secondary adrenal insufficiency with measurements during stable C-HC and 16 weeks after treatment switch to DR-HC. OUTCOMES: Diurnal salivary-cortisol/cortisone, body composition assessed by Dual-Energy X-ray absorptiometry scan, bone status indices (serum type I N-terminal procollagen [PINP], collagen type I cross-linked C-telopeptide [CTX], osteocalcin, receptor activator kappa-B [RANK] ligand, osteoprotegerin, and sclerostin), lipids, haemoglobin A1c (HbA1c), and 24-hour blood pressure. RESULTS: After the switch to DR-HC, the diurnal salivary-cortisol area under the curve (AUC) decreased non-significantly (mean difference: -55.9 nmol/L/day, P = 0.06). The salivary-cortisone-AUC was unchanged. Late-evening salivary-cortisol and cortisone were lower (-1.6 and -1.7 nmol/L, P = 0.002 and 0.004). Total and abdominal fat mass (-1.5 and -0.5 kg, P = 0.003 and 0.02), HbA1c (-1.2 mmol/mol, P = 0.02), and osteocalcin decreased (-7.0 µg/L, P = 0.03) whereas sclerostin increased (+41.1 pg/mL, P = 0.0001). The remaining bone status indices, lipids, and blood pressure were unchanged. CONCLUSION: This study suggests that switching to DR-HC leads to lower late-evening cortisol/cortisone exposure and a more favourable metabolic profile and body composition. In contrast, decreased osteocalcin with increasing sclerostin might indicate a negative impact on bones. CLINICAL TRIAL REGISTRATION: EudraCT201400203932.

Glucose metabolism, gut-brain hormones, and acromegaly treatment: an explorative single centre descriptive analysis.

PURPOSE: Active acromegaly is associated with impaired glucose metabolism, which improves upon treatment. Treatment options include surgery, medical therapy with somatostatin analogues (SSA) and Pegvisomant (PEG), and irradiation. The objective of the study was to describe the differential effect of various treatment regimens on the secretion of glucose, insulin, glucagon, glucagon-like peptide-1 (GLP-1), and glucose-dependent insulinotropic polypeptide (GIP) in patients with acromegaly. METHODS: 23 surgically treated, non-diabetic patients with acromegaly and 12 healthy controls underwent an oral glucose tolerance test (OGTT) and subsequently isoglycaemic intravenous glucose infusion on a separate day. Baseline hormone concentrations, time-to-peak and area under the curve (AUC) on the OGTT-day and incretin effect were compared according to treatment regimens. RESULTS: The patients treated with SSA (N = 15) had impaired GIP-response (AUC, P = 0.001), and numerical impairment of all other hormone responses (P > 0.3). Patients co-treated with PEG (SSA + PEG, N = 4) had increased secretion of insulin and glucagon compared to patients only treated with SSA (SSA ÷ PEG, N = 11) (insulinAUC mean ± SEM, SSA + PEG 49 ± 8.3 nmol/l*min vs SSA ÷ PEG 25 ± 3.4, P = 0.007; glucagonAUC, SSA + PEG 823 ± 194 pmol/l*min vs SSA ÷ PEG 332 ± 69, P = 0.009). GIP secretion remained significantly impaired, whereas GLP-1 secretion was numerically increased with PEG (SSA + PEG 3088 ± 366 pmol/l*min vs SSA ÷ PEG 2401 ± 239, P = 0.3). No difference was found in patients treated with/without radiotherapy nor substituted or not with hydrocortisone. CONCLUSION: SSA impaired the insulin, glucagon, and incretin hormone secretions. Co-treatment with PEG seemed to counteract the somatostatinergic inhibition of the glucagon and insulin response to OGTT. We speculate that PEG may exert its action through GH-receptors on pancreatic δ-cells. Clinical trial registration NCT02005978.