Dose response of inhaled corticosteroids on bronchial hyperresponsiveness: a meta-analysis.
BACKGROUND
There is a relatively steep dose-response curve for effects of inhaled corticosteroids on conventional airway markers of asthmatic disease control.


OBJECTIVE
We sought to determine whether a dose-response effect exists for bronchial hyperresponsiveness.


METHODS
A meta-analysis of placebo-controlled trials in asthmatic patients was performed using a computerized systematic review of databases. Doubling dose/dilution protection of inhaled corticosteroid was compared with placebo. Studies which used direct (methacholine and histamine) and indirect (adenosine monophosphate) bronchial challenge stimuli were eligible for inclusion.


RESULTS
Twenty-five studies fulfilled eligibility criteria (963 patients). Values for doubling dose/dilution protection categorized by low/medium dose (< 1,000 microg) and high dose (> or = 1,000 microg) of inhaled corticosteroid amounted to a 1.25 (95% confidence interval 1.08 to 1.42) and 2.16 (95% confidence interval 1.88 to 2.44) shift, respectively.


CONCLUSIONS
High doses of inhaled corticosteroids conferred greater improvements in bronchial hyperresponsiveness than low doses.
Currie
Graeme P
GP
Asthma and Allergy Research Group, Ninewells Hospital and Medical School, University of Dundee, Dundee, Scotland, United Kingdom.
Fowler
Stephen J
SJ
Lipworth
Brian J
BJ
D000280:Administration, Inhalation; D018927:Anti-Asthmatic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D000893:Anti-Inflammatory Agents / Q000008:administration & dosage* / Q000627:therapeutic use*; D001249:Asthma / Q000188:drug therapy*; D016535:Bronchial Hyperreactivity / Q000188:drug therapy / Q000503:physiopathology*; D001985:Bronchial Provocation Tests; D016085:Bronchoconstrictor Agents; D004305:Dose-Response Relationship, Drug; D006801:Humans; D016032:Randomized Controlled Trials as Topic / Q000379:methods; D013256:Steroids; D016896:Treatment Outcome
D018927:Anti-Asthmatic Agents; D000893:Anti-Inflammatory Agents; D016085:Bronchoconstrictor Agents; D013256:Steroids