Predisposition to acute respiratory infections among overweight preadolescent children: an epidemiologic study in Poland.

This cross-sectional field health survey has as its subjects 1129 preadolescent children resident in Krakow. Trained health visitors interviewed the mothers at the children's schools or at the parents' homes in order to gather standardized information regarding the families' social background and the families' and children's respiratory health and episodes of respiratory infections. Predisposition to respiratory infections in children has been defined as frequent spells (3 or more) of acute respiratory infections experienced by a given child over the 12 months preceding the interview. Clinical examination of children consisted of anthropometric measurements and spirometric testing. Anthropometric measurements (weight and height) were used for calculation of the body mass index (kg/m2). A child whose BMI was 20 or higher was defined as overweight (90th percentile). Susceptibility to acute respiratory infections was related significantly to body mass index. The children with BMI > or = 20 experienced twice as high a risk for acute respiratory infections than children with low BMI (OR = 2.02, 95% CI: 1.13-3.59). Out of other potential factors possibly involved in the occurrence of respiratory infections only the presence of chronic respiratory symptoms (OR = 2.43, 95% CI: 1.64-3.59), allergy (OR = 1.89, 95% CI: 1.34-2.66), and Environmental Tobacco Smoke (OR = 1.54; 95% CI: 1.05-2.25) increased the susceptibility of children to acute respiratory infections. Central heating in the household was shown to have a protective effect (OR = 0.65, 95% CI: 0.43-1.00) when compared with children from households where coal or gas was used for home heating.