Newcastle researchers say they have found a link between asthma and oestrogen in young obese women.
The Hunter Medical Research Institute's Hayley Scott says oestrogen stimulates leptin, a hormone that regulates hunger, but also promotes airway inflammation.
A study of 130 people found younger females tended to show a more hormone-related pattern of airway inflammation that is associated with higher levels of oestrogen.
Dr Scott says obesity is known to be a major risk factor for asthma but the relationship is not well understood.
"There is potential to modulate sex hormone levels in obese young women with asthma for improved management of their respiratory condition," she said.
"Neutrophilia (a form of airway inflammation) doesn't respond well to frontline asthma treatment with inhalers."
The findings were presented in Darwin at the annual scientific meeting of the Thoracic Society of Australia and New Zealand.
Link to online findings here.