Eur J Endocrinol. 2025 Oct 15:lvaf215. doi: 10.1093/ejendo/lvaf215. Online ahead of print.
ABSTRACT
DESIGN: Morning cortisol predicts the outcome of the short synacthen test (SST). There is a paucity of studies examining this in a dedicated cohort of children and adults weaning off glucocorticoids and using a modern immunoassay. This study aimed to identify early morning serum cortisol (EMC) cut-offs which predict the SST outcome in children and adults during glucocorticoid weaning.
METHODS: A retrospective cohort study of paediatric and adult patients on long-term glucocorticoids with suspected glucocorticoid-induced adrenal insufficiency (GIAI) undergoing an SST. Our main outcomes were cut offs with 95% and 99% sensitivity and specificity for EMC analysed on modern immunoassays, determined via receiver operating characteristic (ROC) curve analysis. A pass on SST was defined as 30-minute cortisol of ≥430 nmol/L (15.6 µg/dL).
RESULTS: 151 and 372 SSTs were included in the paediatric and adult cohorts, respectively, of which 32% and 37% were passed. ROC curve analysis demonstrated that EMC performed well in both cohorts with area under curve (AUC) of 0.79 (95%CI 0.71,0.87) and 0.88 (95%CI 0.84,0.91), respectively. EMC cut offs to predict a pass on SST were 278 (10.1 µg/dL) and 290 nmol/L (10.5 µg/dL) at 95% sensitivity, and 316 (11.5 µg/dL) and 349 nmol/L (12.7 µg/dL) at 99% sensitivity, respectively. Further analysis in adults showed that using 95% cut off in clinical practice was effective as 48/51 patients with EMC between 290-349nmol/L (10.5-12.7 µg/dL), were weaned without adverse events.
CONCLUSION: Morning serum cortisol can predict the SST outcome in children and adults weaning from glucocorticoids. An EMC>290 nmol/L in adults predicts a patient can wean glucocorticoid therapy and will recover adrenal function.
PMID:41092479 | DOI:10.1093/ejendo/lvaf215
