Smoke Exposure in Infancy May Cause Atopic Sensitization
Study reports IgE sensitization to common allergens in children whose parents smoked
THURSDAY, Dec. 20 (HealthDay News) -- Children exposed to secondhand cigarette smoke in early infancy may be at increased risk of developing atopic sensitization to common inhalant and food allergens, according to an article published online Dec. 18 in Thorax.
Eva Lannero, of Karolinska University Hospital in Stockholm, Sweden, and colleagues followed 4,089 Swedish families to investigate the effect of prenatal and postnatal smoking exposure on IgE sensitization. Families answered questionnaires on environmental factors when the child was 2 months, and again at 1, 2 and 4 years old. Blood drawn at age 4 from 2,614 children was analyzed for IgE antibodies to common inhalant and food allergens.
Smoke exposure during early infancy was associated with IgE sensitization in a dose-response manner. Children exposed to smoke at 2 months of age had an increased risk of sensitization to inhalant and/or food allergens (odds ratio 1.28), particularly for cat allergens (OR, 1.96) and food allergens (OR, 1.46). Prenatal smoke exposure was not associated with IgE sensitization.
The authors write, "our data support the 'mucosal concept of atopy,' which implies that sensitization occurs mainly in the mucosal surfaces of the airways and that mucosal damage and inflammation facilitate sensitization. It is noteworthy that smoke exposure appeared to facilitate sensitization to the perennial indoor allergens, such as cat, and not to the same extent sensitization to seasonal pollen allergens to which we are mainly exposed outdoors where the inhaled dose of tobacco smoke exposure is limited."