TY - JOUR
T1 - Improving the interpretation of afternoon cortisol levels and SSTs to prevent misdiagnosis of adrenal insufficiency
AU - Ramadoss, Vijay
AU - Lazarus, Katharine
AU - Prevost, Andrew Toby
AU - Tan, Tricia
AU - Meeran, Karim
AU - Choudhury, Sirazum
N1 - Funding Information:
SC is funded by a National Institute for Health Research (NIHR), Doctoral Research Fellowship (Grant: DRF-2017-10-115) and the Imperial Health Charity. KM is funded by the NIHR BRC. TT is funded by the NIHR, NIHR BRC and the Moulton Charitable Research Foundation. ATP is funded by the Higher Education Funding Council for England (HEFCE).
Publisher Copyright:
© The Author(s) 2021.
PY - 2021/11/1
Y1 - 2021/11/1
N2 - Background: Adrenal Insufficiency (AI), especially iatrogenic-AI, is a treatable cause of mortality.The difficulty in obtaining 9 am cortisol levels means samples are taken at suboptimal times, including a substantial proportion in the afternoon. Low afternoon cortisol levels often provoke short Synacthen tests (SSTs). It is important that this does not lead to patients misdiagnosed with AI, exposing them to the excess mortality and morbidity of inappropriate steroid replacement therapy. Methods: This retrospective study collected 60 178 cortisol results. Medical records, including subsequent SSTs of initial cortisol results measured after midday were reviewed. Results: Receiver operating characteristic analysis (area under the curve: 0.89) on 6531 suitable cortisol values showed that a limit of <201.5 nmol/L achieved a sensitivity and specificity of 95.6% and 72.6%, while a limit of <234 nmol/L had a sensitivity of 100% and a specificity of 59.5%. Out of 670 SSTs, 628 patients passed. Of these, 140 would have otherwise failed if only their 30-min cortisol was assessed without the 60-min value. A 30- and 60-min SST cortisol cutoff of 366.5 nmol/L and 418.5 nmol/L, respectively, can achieve a sensitivity of >95% on the Abbott analyser platform. Conclusion: An afternoon cortisol >234 nmol/L excludes AI on Abbott analyser platforms. In patients who have an afternoon cortisol <234 nmol/L, including both 30- and 60-min SST cortisol values prevents unnecessary glucocorticoid replacement therapy in 22.3% of individuals in this study.The Abbott analyser SST cortisol cutoffs used to define AI should be 366.5 nmol/L and 418.5 nmol/L at 30 and 60 min, respectively. All patients remained well subsequently with at least 1-year longitudinal follow-up.
AB - Background: Adrenal Insufficiency (AI), especially iatrogenic-AI, is a treatable cause of mortality.The difficulty in obtaining 9 am cortisol levels means samples are taken at suboptimal times, including a substantial proportion in the afternoon. Low afternoon cortisol levels often provoke short Synacthen tests (SSTs). It is important that this does not lead to patients misdiagnosed with AI, exposing them to the excess mortality and morbidity of inappropriate steroid replacement therapy. Methods: This retrospective study collected 60 178 cortisol results. Medical records, including subsequent SSTs of initial cortisol results measured after midday were reviewed. Results: Receiver operating characteristic analysis (area under the curve: 0.89) on 6531 suitable cortisol values showed that a limit of <201.5 nmol/L achieved a sensitivity and specificity of 95.6% and 72.6%, while a limit of <234 nmol/L had a sensitivity of 100% and a specificity of 59.5%. Out of 670 SSTs, 628 patients passed. Of these, 140 would have otherwise failed if only their 30-min cortisol was assessed without the 60-min value. A 30- and 60-min SST cortisol cutoff of 366.5 nmol/L and 418.5 nmol/L, respectively, can achieve a sensitivity of >95% on the Abbott analyser platform. Conclusion: An afternoon cortisol >234 nmol/L excludes AI on Abbott analyser platforms. In patients who have an afternoon cortisol <234 nmol/L, including both 30- and 60-min SST cortisol values prevents unnecessary glucocorticoid replacement therapy in 22.3% of individuals in this study.The Abbott analyser SST cortisol cutoffs used to define AI should be 366.5 nmol/L and 418.5 nmol/L at 30 and 60 min, respectively. All patients remained well subsequently with at least 1-year longitudinal follow-up.
KW - Adrenal insufficiency
KW - Cortisol
KW - Hypocortisolemia
KW - Short Synacthen test
UR - http://www.scopus.com/inward/record.url?scp=85117319692&partnerID=8YFLogxK
U2 - 10.1210/jendso/bvab147
DO - 10.1210/jendso/bvab147
M3 - Article
AN - SCOPUS:85117319692
SN - 2472-1972
VL - 5
JO - Journal of the Endocrine Society
JF - Journal of the Endocrine Society
IS - 11
M1 - bvab147
ER -