title: Oral and inhaled corticosteroids and adrenal insufficiency: a case-control study.
abstract: BACKGROUND
  Adrenal insufficiency, a well recognised complication of treatment with oral corticosteroids, has been described in association with inhaled corticosteroid use in over 60 case reports. The risk of adrenal insufficiency in people prescribed an oral or inhaled corticosteroid in the general population is not known. A study was undertaken to quantify the association between adrenal insufficiency and oral and inhaled corticosteroid exposure.
  
  
  METHODS
  A case-control study was performed using computerised general practice data from The Health Improvement Network.
  
  
  RESULTS
  From a cohort of 2.4 million people, 154 cases of adrenal insufficiency and 870 controls were identified. There was a dose related increased risk of adrenal insufficiency in people prescribed an oral corticosteroid with an odds ratio of 2.0 (95% CI 1.6 to 2.5) per course of treatment per year. Adrenal insufficiency was associated with a prescription for an inhaled corticosteroid during the 90 day period before the diagnosis with an odds ratio of 3.4 (95% CI 1.9 to 5.9) and this effect was dose related (p for trend <0.001). After adjusting for oral corticosteroid exposure, this odds ratio was reduced to 1.6 (95% CI 0.8 to 3.2) although the dose relation remained (p for trend 0.036).
  
  
  CONCLUSIONS
  People prescribed an oral or inhaled corticosteroid are at a dose related increased risk of adrenal insufficiency although the absolute risk is small. This analysis suggests that the increased risk in people prescribed an inhaled corticosteroid is largely due to oral corticosteroid exposure, but inhaled corticosteroids may have an effect when they are taken at higher doses.
authors.affiliation: Division of Respiratory Medicine, Nottingham City Hospital, Nottingham NG5 1PB, UK. Kevinmortimer@msn.com
authors.forename: K J
authors.initials: KJ
authors.lastname: Mortimer
authors.forename: L J
authors.initials: LJ
authors.lastname: Tata
authors.forename: C J P
authors.initials: CJ
authors.lastname: Smith
authors.forename: J
authors.initials: J
authors.lastname: West
authors.forename: T W
authors.initials: TW
authors.lastname: Harrison
authors.forename: A E
authors.initials: AE
authors.lastname: Tattersfield
authors.forename: R B
authors.initials: RB
authors.lastname: Hubbard
mesh_terms: D000280:Administration, Inhalation; D000284:Administration, Oral; D000293:Adolescent; D000305:Adrenal Cortex Hormones / Q000008:administration & dosage / Q000009:adverse effects*; D000309:Adrenal Insufficiency / Q000139:chemically induced*; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged
chemical_list: D000305:Adrenal Cortex Hormones