Researchers have known for years that obesity and breathing problems like asthma were linked, and now they have a good idea why.
A study published in the May issue of the American Journal of Respiratory and Critical Care Medicine points to significant differences in lung function among asthmatic women with varying body mass index numbers. Obese women appear to be more prone to "dynamic hyperinflation," a condition in which air breathed into the lungs becomes trapped and cannot be exhaled. These women thus may have more trouble breathing during an asthma attack than do nonobese women. "They may experience more shortness of breath and, compared with nonobese patients, are closer to severely exacerbating an asthma attack," says John Heffner, the immediate past president of the American Thoracic Society and a specialist in pulmonary and critical care medicine in Oregon.
With rates of both obesity and asthma at worrisome levels, an effort is underway this month to counter underdiagnosis and undertreatment. For the 12th year, the American College of Allergy, Asthma, and Immunology is offering free screening exams with asthma specialists at 250 locations across the country.
"This year, we will be targeting people who have already been diagnosed with asthma but who may not be controlling their disease and want a '50,000-mile tune-up,'" says John Winder, chair of the program and an allergist in Toledo, Ohio. The program, sponsored by drug company AstraZeneca, which makes asthma medication, also has specially geared tests for children. More information on diagnosis and screening locations can be found on the ACAAI website.