Obesity Alters Airway Muscle Function, Increases Asthma Risk

New research suggests that obesity changes how airway muscles function, increasing the risk of developing asthma. The study is published ahead of print in the American Journal of Physiology–Lung Cellular and Molecular Physiology.

The prevalence of asthma and obesity–as both separate and coexisting conditions–has grown considerably in the U.S. in recent years. Obesity is a major risk factor for asthma, in part because of the systemic and localized inflammation of the airways that occurs in people with a high body mass index.

People with obesity “also manifest a higher risk of severe asthma, decreased disease control and decreased response to corticosteroids therapy,” explained the bicoastal team of scientists who conducted the research. However, previous studies suggest that some people with obesity may have a type of asthma that is not caused by airway inflammation, but by hyperresponsiveness–a higher-than-normal response to an allergen–in the airway smooth muscle. Hyperresponsiveness causes the airways to narrow, obstructing ease of breathing, and can occur when the muscles contract or begin to spasm.