Shaving off extra kilos might help asthmatic kids prevent flares of the disease, according to a study that found that obese children have a harder time controlling their symptoms.
The work is the first to show that even after taking race and social factors into account, heavier kids use more drugs to control their asthma and curb exacerbation than slimmer kids.
"Improving nutritional status, preventing obesity, and stressing the importance of weight loss might improve asthma control and exacerbation risk in children and decrease the incidence of asthma in adults," researchers wrote in the Journal of Allergy and Clinical Immunology.
Both asthma and obesity rates have soared among kids in recent decades, reaching nearly 10% and 17%, respectively.
While some studies have hinted at a link between the two conditions, conclusions on whether heavier kids also have more severe asthma than others have been mixed.
Dr Kenneth B. Quinto from the University of California, San Diego, and colleagues looked back at more than 32,000 children with asthma who were enrolled in a Kaiser Permanente health plan. Nearly half the children were overweight (BMI percentile for age, 85% to 94%) or obese (BMI percentile for age, 95% or higher).
Heavy youngsters use more inhaled steroids
The researchers found on average, normal-weight children used 2.8 rescue inhalers a year, whereas obese kids used 3.1. The heavy youngsters also used more inhaled steroids.
And the results held up after Dr Quinto and his colleagues accounted for such possible confounding factors as sex, race, diabetes and parents' education levels.
The team speculates that the extra kilos might be weighing on the lungs, making obese kids feel like they need more medication. Scientists have also found that overweight people don't respond as well as others to steroids, which might help explain the new findings.
Still, in an observational study like theirs, the researchers warn it's never possible to be certain of cause and effect, so whether bigger waistlines should be blamed for more exacerbation remains an open question.
Meanwhile, the team writes, "The best time for prevention of obesity and nonsurgical weight reduction likely occurs in childhood."
(Reuters Health, September 2011)