title: Outcomes after periodic use of inhaled corticosteroids in children.
abstract: BACKGROUND
  Many children with persistent asthma use inhaled corticosteroids on a periodic basis. Clinical trials in adults suggest that periodic use of inhaled corticosteroids may be effective for patients with mild persistent asthma. However, scant information exists on the clinical outcomes of children with asthma who are using inhaled corticosteroids on a periodic basis in real-world settings.
  
  
  OBJECTIVE
  This prospective cohort study compared clinical outcomes during a 12-month follow-up period between children with persistent asthma whose parents believed that they were supposed to use inhaled steroids either (a) periodically or (b) daily year-round at the start of the period. The clinical outcomes studied were (1) asthma-related emergency department (ED) visits or hospitalizations, (2) uncontrolled asthma based on health care and medication use, and (3) outpatient visits for asthma.
  
  
  METHODS
  The study population included children with persistent asthma from two health plans whose parents reported that they were using inhaled corticosteroids during a baseline telephone interview. The interviews collected information on whether the children's parents believed they were supposed to use inhaled corticosteroids on a periodic or daily basis, as well as baseline asthma symptom status, sociodemographic, and behavioral variables. We used computerized databases to identify clinical events for each child during the 12 months after their baseline interview. Uncontrolled asthma was defined as any asthma-related ED visit or hospitalization, two or more oral steroid prescription fills, or four or more beta-agonists canisters filled during the 12-month period. We compared these outcomes between the periodic versus daily users of inhaled corticosteroids using logistic regression analyses. We conducted both (1) a traditional logistic regression analysis in which we adjusted for selection bias by including covariates such as age, asthma physical status, sociodemographic and behavioral variables, and history of asthma-related health care use during the year before interview and (2) an analysis using propensity scores to more fully adjust for selection bias.
  
  
  RESULTS
  Of a total of 476 children in the study, 55% of parents believed their children were supposed to be using inhaled corticosteroids on a periodic basis and 45% believed their children were supposed to be using them daily year-round based on the baseline parent interview. At baseline, periodic inhaled corticosteroid users had less severe asthma than daily users based on several measures including better asthma physical status scores on the Children's Health Survey for Asthma (mean 87 +/- 16.0 vs. 81 +/- 17.4, p = < 0.0001). During the year before the baseline interview, periodic users compared with daily users were less likely to have an ED visit or hospitalization (10% vs. 23%, p = 0.0001) and less likely to have had five or more albuterol prescription fills (13% vs. 31%, p < 0.0001). During the follow-up year, those who believed inhaled steroids were for periodic use were less likely than those who believed inhaled steroids were for daily use to have an ED visit or hospitalization for asthma (OR 0.36, 95% CI: 0.18-0.73), even after adjusting for baseline asthma status and other covariates. Similarly, those who believed inhaled steroids were for periodic use were less likely to have uncontrolled asthma, OR 0.38 (95% CI: 0.24-0.62). Analyses using propensity score adjustment yielded similar results to the logistic regression analyses.
  
  
  CONCLUSIONS
  Children whose parents believed they were supposed to use inhaled corticosteroids on a periodic basis had less severe asthma at baseline than those whose parents believed they were supposed to be using them daily. Periodic users were less likely than daily users to have adverse asthma outcomes during 1-year follow-up. This suggests that clinicians may be applying appropriate selection criteria by choosing patients with less severe asthma for periodic inhaled corticosteroid regimens.
authors: Center for Child Health Care Studies, Department of Ambulatory Care and Prevention, Harvard Medical School, 133 Brookline Avenue, 6th Floor, Boston, MA 02215, USA. ann.wu@childrens.harvard.edu
authors: Ann Chen
authors: AC
authors: Wu
authors: Lingling
authors: L
authors: Li
authors: Irina
authors: I
authors: Miroshnik
authors: James
authors: J
authors: Glauber
authors: Charlene
authors: C
authors: Gay
authors: Tracy A
authors: TA
authors: Lieu
mesh_terms: D000280:Administration, Inhalation; D000318:Adrenergic beta-Agonists / Q000008:administration & dosage; D001249:Asthma / Q000188:drug therapy*; D002648:Child; D004334:Drug Administration Schedule; D004363:Drug Utilization; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data; D005260:Female; D005938:Glucocorticoids / Q000008:administration & dosage / Q000627:therapeutic use*; D006296:Health Services / Q000706:statistics & numerical data*; D006760:Hospitalization / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012959:Socioeconomic Factors; D016896:Treatment Outcome
chemical_list: D000318:Adrenergic beta-Agonists; D005938:Glucocorticoids