Inhaled corticosteroids and HPA axis suppression: how important is it and how should it be managed?

Area of Science:

• Pulmonology
• Endocrinology

Background:

• Inhaled corticosteroids (ICS) are primary treatments for bronchoconstrictive lung diseases.
• Systemic absorption of ICS can lead to hypothalamic-pituitary-adrenal (HPA) axis suppression in some patients.
• HPA axis suppression is often undetected and can lead to adrenal crisis during physical stress.

Purpose of the Study:

• To highlight the risk of HPA axis suppression from ICS.
• To identify patient groups at higher risk for this adverse effect.
• To recommend strategies for minimizing and managing HPA axis suppression.

Main Methods:

• Review of existing literature on ICS and HPA axis function.
• Identification of risk factors for ICS-induced HPA axis suppression.
• Analysis of clinical scenarios where HPA axis suppression presents.

Main Results:

• HPA axis suppression is a recognized complication of ICS therapy.
• Higher cumulative ICS doses, concurrent oral corticosteroids, and CYP3A4 inhibitors increase risk.
• Adrenal crisis during stress is a common presentation, particularly in children.

Conclusions:

• 'Higher risk' patients require education on sick day rules to prevent adrenal crisis.
• Regular review of ICS therapy to ensure minimum effective dosage is essential.
• Synacthen testing can identify patients with pre-existing suppressed cortisol responses.