Aging does not affect beta-agonist responsiveness after methacholine-induced bronchoconstriction.

Abstract

OBJECTIVES: To assess the response to an inhaled beta-agonist alone or in combination with an anticholinergic agent after methacholine-induced bronchoconstriction in four age groups. DESIGN: Retrospective analysis. SETTING: Pulmonary function laboratory in a university-affiliated hospital. PARTICIPANTS: Seven hundred sixty-four consecutive subjects with a 20% reduction or more in forced expiratory volume during the first second (FEV1) of exhalation from total lung capacity after inhaling 189 or fewer cumulative units of methacholine were included in the analysis. INTERVENTION: The first 382 subjects received three inhalations of metaproterenol (total of 1.95 mg), and the other 382 subjects received three inhalations of albuterol and ipratropium combination (total of 309 microg of albuterol and 54 microg of ipratropium) after methacholine-induced bronchoconstriction. MEASUREMENTS: The response to bronchodilators was assessed as the postbronchodilator percentage change in FEV1 and the percentage of subjects recovering to 90% or better of baseline FEV1 after the use of bronchodilator. RESULTS: The percentage change in FEV1 postbronchodilator in the elderly was similar to that of the younger subjects. The percentage of subjects who recovered to 90% or better of their baseline FEV1 postbronchodilator was also similar in the elderly and younger age groups. Response to metaproterenol was similar to that of the albuterol/ipratropium combination in all age groups (all P>.05). CONCLUSION: Aging does not affect bronchodilator response to beta-agonist after methacholine-induced bronchoconstriction. The responsiveness to beta-agonist alone is similar to the responsiveness to the combination of beta-agonist and anticholinergic agent in all age groups.