LOS ANGELES, Nov. 15 (UPI) -- Teens who smoke cigarettes regularly increase their risk of developing asthma compared to their non-smoking peers, says a U.S. study.
Dr. Frank D. Gilliland of the Keck School of Medicine at the University of Southern California and colleagues analyzed 2,609 children with no prior history of either asthma or wheezing.
All participants were recruited from fourth- and seventh-grade classrooms in 12 southern California communities. Among the children studied, there were 255 cases of new-onset asthma -- 104 males and 151 females. Children who reported smoking 300 or more cigarettes per year had almost a four-fold increased risk for new-onset asthma compared with non-smokers, but surprisingly, this increased risk was greater in non-allergic children than those with a history of allergies, according to Gilliland.
The adolescents most at risk for developing asthma are those who were exposed to cigarette smoke while in the womb and who later became regular smokers of seven or more cigarettes per day -- this combination led to more than an eight-fold increased risk of asthma compared with unexposed non-smokers, according to the study published in the American Journal of Respiratory and Critical Care Medicine.
