Paradoxical bronchoconstriction occurs in 5% of COPD patients treated with beta-2-agonists

African–American patients with COPD are more likely to be affected by therapy-induced bronchoconstriction, study suggests.

African-American male patient with chronic obstructive pulmonary disease

Beta₂ agonist drugs are used for their bronchodilatory properties in chronic obstructive pulmonary disease (COPD), yet a paradoxical bronchoconstrictive effect, resulting in respiratory distress, occurs in some people.

The first systematic study of responses to beta₂ agonists has identified paradoxical bronchoconstriction in 5% of nearly 10,000 patients with COPD. A paradoxical response was twice as common in African–American patients than in other racial groups, and was also associated with worse respiratory outcomes, including more severe dyspnoea, shorter six-minute walk distance and more frequent severe exacerbations.

“These findings might have implications for the use of beta₂ agonists in some patients,” conclude Surya Bhatt, from the University of Alabama in Birmingham, and colleagues writing in The Lancet Respiratory Medicine (online, 10 September 2014).^[1]