The Contribution of Oral and Inhaled Glucocorticoids to Adrenal Insufficiency in Asthma

• Published in: The journal of allergy and clinical immunology in practice (Cambridge, MA)
• Main Authors: Brennan, Vincent, Martin-Grace, Julie, Greene, Garrett, Heverin, Karen, Mulvey, Christopher, McCartan, Tom, Lombard, Lorna, Walsh, Joanne, Hale, Elaine Mac, Srinivasan, Shari, O'Reilly, Michael W, Thompson, Chris J, Costello, Richard W, Sherlock, Mark
• Format: Journal Article
• Language: English
• Published: United States 01.10.2022
• Subjects: adrenal insufficiency; Cortisol; inhaled glucocorticoids; corticosteroids; oral glucocorticoids; synacthen
• ISSN: 2213-2201
• DOI: 10.1016/j.jaip.2022.05.031

Exposure to any form of glucocorticoid preparation is associated with a risk of adrenal insufficiency (AI). We aimed to establish the contribution of oral corticosteroids (OCS) and inhaled corticosteroids (ICS) exposure to the risk of AI in a cohort of patients (n= 80) with severe, uncontrolled asthma. We compiled individualised cumulative OCS and ICS exposure data using a combination of healthcare records and electronic inhaler monitoring using an Inhaler Compliance Assessment (INCA™) device and estimated the risk of AI for each participant using a morning serum cortisol concentration. The predicted prevalence of AI was based on morning cortisol concentrations was 25% (20/80). Participants on maintenance OCS therapy had the highest risk of AI at 60% (6/10) compared to 17% (11/65) in those with no recent OCS exposure. Morning serum cortisol correlated negatively with both OCS exposure (mg/kg prednisolone) (r=-0.4, p<0.0002) and ICS exposure (mg/kg fluticasone propionate (FP) (r=-0.26, p=0.019). Logistic regression of risk of AI against the number of standard treatment courses of OCS demonstrated a positive relationship although this did not reach statistical significance.[OR 1.41(CI 0.97-2.05,p=0.073)]. Logistic regression analysis, categorising patients as high-risk AI(cortisol<130nmol/l) or not(cortisol>130nmol/l), showed that cumulative ICS exposure remained a significant predictor of AI, even when exposure to OCS was controlled for [OR 2.17 per 1mg/kg increase in cumulative FP exposure,(CI 1.06-4.42) p=0.033]. Our data suggests that AI is common amongst patients with asthma and highlights that the risk of AI is associated with both high dose ICS therapy and intermittent treatment courses of OCS.