HealthDay News – The development of allergic diseases such as asthma, rhinitis, and eczema are linked to in utero or early childhood exposure to secondhand smoke according to a study published in Pediatrics.
“Many children are exposed to tobacco smoke both in utero and postnatally,” explained Jesse D. Thacher, MPH, of the Karolinska Institutet in Stockholm, and colleagues. “[U]p to 60% of mothers who quit smoking during pregnancy return to smoking within the first six months postpartum, and 80%-90% relapse less than 12 months after delivery.”
To assess the association between secondhand smoke exposure and the development of allergic diseases during the first 16 years of life, the investigators followed a birth cohort of 4,089 patients for 16 years.
Exposure to secondhand smoke during infancy was associated with an overall elevated risk of asthma (OR=1.23; 95% CI:1.01–1.51), rhinitis (OR=1.18; 95% CI:1.01–1.39), and eczema (OR=1.26; 95% CI:1.09–1.45) for up to 16 years, reported the inspectors.
The elevated risks associated with secondhand smoke exposure in utero or during infancy were mostly confined to early childhood for asthma and rhinitis, whereas the excess risk of eczema appeared greatest at later ages.
“Our findings indicate that early secondhand smoke exposure, in utero or during infancy, influences the development of allergic disease up to adolescence,” concluded the researchers.