Asthma and obesity in three-year-old urban children: role of sex and home environment.

Objective: To examine whether the relationship between obesity and asthma in young girls and boys can be explained by social and physical characteristics of the home environment.

Study Design: We examined the relationship between asthma and obesity in children in the Fragile Families and Child Wellbeing Study (n=1815). Asthma was determined through maternal report of asthma diagnosis by a doctor (active in past 12 months). Weight and height of child was measured during an in-home visit. Data on home social (maternal depression, intimate partner violence) and physical environmental factors (housing quality, tobacco exposure) were collected via questionnaire.

Results: Ten percent of children had active asthma, 19% of children were overweight, and 17% of children were obese. In fully adjusted models, obese children had twice the odds of having asthma (OR, 2.3; 95% CI, 1.5-3.3) compared with children of normal body weight. In stratified analyses, overweight boys, but not overweight girls, had increased of odds of asthma. Obese boys and girls had increased odds of asthma compared with boys and girls of normal body weight.

Conclusion: The relationship between asthma and obesity is present in boys and girls as young as 3 years of age; a relationship between being overweight and asthma is only present among boys. This relationship is not attributable to shared social and environmental factors of the children's home.