Formal Correction: This article has been formally corrected to address the following errors.
Citation: Phelps J 2004. Obesity and Asthma Risk in School-Age Children. Environ Health Perspect 112:a164-a164.
Gilliland FD, Berhane K, Islam T, McConnell R, Gauderman WJ, Gilliland SS, Avol E, Peters JM. 2003. Obesity and the risk of newly diagnosed asthma in school-age children. Am J Epidemiol 158:406-415.
Both asthma and obesity have been rapidly increasing in incidence among children in the past 20 years. Health care providers have explained this association as evidence that children with asthma are less likely to engage in physical activity and therefore more prone to gain weight. However, this interpretation has been challenged in recent studies, including this work by an NIEHS-supported research team from the University of Southern California.
The team studied the association of newly diagnosed asthma and the development of obesity using data collected at yearly assessments over a six-year period. The data were gathered as part of the Children's Health Study of Southern California, a longitudinal study of respiratory health among nearly 3,800 youngsters aged 7-18. Most of the children were white or Hispanic. About 20% had a history of physician-diagnosed allergy; 24% of the boys and 21% of the girls reported ever experiencing wheeze.
The data revealed that new-onset asthma was diagnosed about 1.5 times more often among overweight and obese children. Boys had a slightly higher risk of about twofold. Interestingly, the effect of being overweight was about twice as high in nonallergic children as in children with documented allergies (the authors note, however, that this difference may be due in part to an underreporting of allergy).
These findings may have important public health implications in the battle to control the epidemics of both asthma and obesity in children. During the last decade alone, the prevalence of overweight in U.S. children has increased by 40%. If being overweight does indeed contribute to developing asthma, public health professionals may need to target obesity prevention in their efforts to control asthma. Further longitudinal epidemiologic and mechanistic studies are necessary to confirm these results and to identify all causes of the childhood asthma epidemic.