Prevalence of hypothalamic-pituitary-adrenal axis suppression in children treated for asthma with inhaled corticosteroid.

OBJECTIVE

To determine the prevalence of hypothalamic-pituitary-adrenal (HPA) axis suppression in asthmatic children on inhaled corticosteroids (ICS).

METHODS

Clinical and demographic variables were recorded on preconstructed, standardized forms. HPA axis suppression was measured by morning serum cortisol levels and confirmed by low-dose adrenocorticotropic hormone stimulation testing.

RESULTS

In total, 214 children participated. Twenty children (9.3%, 95% CI 5.3% to 13.4%) had HPA axis suppression. Odds of HPA axis suppression increased with ICS dose (OR 1.005, 95% CI 1.003 to 1.009, P<0.001). All children with HPA axis suppression were on a medium or lower dose of ICS for their age (200 μg/day to 500 μg/day). HPA axis suppression was not predicted by drug type, dose duration, concomitant use of long-acting beta-agonist or nasal steroid, or clinical features.

CONCLUSION

Laboratory evidence of HPA axis suppression exists in children taking ICS for asthma. Children should be regularly screened for the presence of HPA axis suppression when treated with high-dose ICS (>500 μg/day). Consideration should be given to screening children on medium-dose ICS.