PT - JOURNAL ARTICLE AU - Fernando C. Wehrmeister AU - Ana M.B. Menezes AU - Bruno P. Nunes AU - Christian Loret de Mola AU - Natália G. Cofré AU - Paula L. Marco AU - Paula D. Oliveira AU - Helen Gonçalves AU - Maria C. Assunção AU - Ricardo B. Noal AU - Pedro C. Hallal TI - Maternal smoking during pregnancy and wheezing at adolescence: The Pelotas 1993 birth cohort, Brazil DP - 2013 Sep 01 TA - European Respiratory Journal PG - P4331 VI - 42 IP - Suppl 57 4099 - http://erj.ersjournals.com/content/42/Suppl_57/P4331.short 4100 - http://erj.ersjournals.com/content/42/Suppl_57/P4331.full SO - Eur Respir J2013 Sep 01; 42 AB - Background: maternal smoking during pregnancy may impair lung development, increasing the risk of respiratory diseases such as asthma later in life. Aim: to evaluate the association between maternal smoking during pregnancy and wheezing in adolescence (at 11 and 15 years old). Methods: the original cohort comprised 5,249 hospital new born children during the calendar year of 1993 in Pelotas, Brazil. In 2004-5 and 2008-9, all cohort members were sought for follow-up visits. Wheezing was defined as the presence of wheezing in the past 12 months. Number of asthma crises in the same period was collected. Persistent wheezing was present when the subjects related wheezing in the last year at both follow-ups. Smoking during pregnancy was collected at delivery and then analyzed in three categories (never smoker, <20 cigarettes/day and 20+ cigarettes/day). Poisson regression models were performed adjusting for potential confounders and possible mediators. Results: no association of maternal smoking during pregnancy was found with wheezing as dichotomous variables neither at age 11 nor at age 15. However, we found a greater number of wheezing crises at age 15 among those adolescents from mothers who had smoked 20+ cigarettes/day (RR=1.97; CI95% 1.06 – 3.68; p=0.023), even when adjusted for confounders and mediators. In persistent wheezing it was observed a dose-response association according to the number of smoked cigarettes/day by the mother during pregnancy (<20 cigarettes/day PR=1.36 and 20+ cigarettes/day PR=1.61). Conclusions: smoking during pregnancy was not associated with the occurrence of wheezing, but it seems to be important for the severity of wheezing at adolescence.