Asthma symptoms can be made worse by obesity, a new study by researchers in New Zealand has found.
Investigators led by Dr Robin Taylor MD of the University of Otago studied lung function in asthmatic women with various body mass indexes.
The women breathed nebulised methacholine to bring on an asthma-like attack, and they were then assessed for changes in lung function, including measuring how much air remained in the lungs after exhalation, and how much they could breathe in on the next breath.
"We have demonstrated significant differences in the changes in respiratory function that occur with asthmatic bronchoconstriction in relation to obesity," Dr Taylor said.
"After the methacholine challenge, the amount of bronchoconstriction was identical for each of the three groups, but the changes in FRC and IC were greatest in the obese group. This indicated to us that greater dynamic hyperinflation was occurring among obese individuals."
He added that it is "quite counterintuitive" because you may have expected that people with a heavier chest would not develop hyperinflation so easily.
