Background: This study was performed to determine the relationship between overweight [body mass index (BMI) > or = 85th percentile] and asthma as determined by spirometry.
Method: Spirometry was performed according to the American Thoracic Society guidelines, and BMI was calculated. Asthma was defined as a forced expiratory volume in 1 second (FEV1) <80% predicted and FEV1/forced vital capacity (FVC) >5% lower than predicted for age and sex.
Results: One-hundred-nine children (age 14.7 +/- 1.6 years) were enrolled. Eighty children (73%) were African-American, and 29 children (27%) were white. Fifty-eight (53%) children were overweight. Twelve (11%) children, of whom nine (75%) were overweight, met the criteria for asthma. Baseline FEV1 percent predicted (87 +/- 6% vs. 83 +/- 7%, p=0.03), FEV1/FVC (93 +/- 6 vs. 87 +/- 8, p<0.001), and FEV1 percent predicted following albuterol administration (94 +/- 7 vs. 89 +/- 7%, p=0.03) were all lower in overweight children. Children with asthma were almost 1.5 times more likely to be overweight compared with children without asthma (relative risk: 1.49, 95% confidence interval: 1.015-2.17).
Conclusions: Inner-city children are more likely to be overweight compared to the general population. Asthma is a risk factor for overweight in these children.