The children of women who smoke during pregnancy may be predisposed to experiment with tobacco at a young age, suggest preliminary study findings.
"The role of prenatal tobacco exposure has been largely overlooked as a risk factor for the development of tobacco use among youth," said lead author Marie D. Cornelius, PhD. "Our findings indicate that fetal exposure to tobacco may have a significant impact on early initiation of tobacco use in children."
Previous studies have suggested that children exposed to tobacco during development may be at higher risk for conduct disorder and attention deficit hyperactivity disorder. Other studies have suggested these children may be more at risk for language and reading difficulties. But few studies have explored the connection between early tobacco exposure and childhood tobacco experimentation.
Cornelius and colleagues from the University of Pittsburgh School of Medicine and the University of Pittsburgh Medical Center, PA, asked 589 10-year-olds -- more than half of whose mothers smoked an average of 15 cigarettes a day during pregnancy -- if they had ever used tobacco.
The 37 children (6 percent) who answered "yes" were significantly more likely to have been exposed to tobacco in the womb, the researchers found. "The other significant predictors of tobacco experimentation were peer tobacco use, child delinquency, maternal depression, and child depression," said Cornelius.
Most of the children who admitted to using tobacco had only experimented with it: approximately 60 percent of the 37 reported that they had tried smoking only once. The study findings are published in the current issue of the journal Nicotine & Tobacco Research.
Since no statistics from national surveys currently exist on the prevalence of smoking in 10-year-olds (the average age of smoking onset is 14.5 years), Cornelius and colleagues did not compare their findings with national averages. For the purposes of this study, they focused solely on the differences they observed between study participants whose mothers smoked during pregnancy and those who did not, without taking smoking prevalence among a wider population into account.
Animal research suggests several possibilities to explain the potential link between tobacco exposure and early tobacco experimentation. One is that tobacco exposure may damage the developing brain of a fetus. "The resulting central nervous system damage may later be expressed as impulsivity, inattention, aggression, depression, and/or anxiety and may create a vulnerability in the child that could contribute to poorer adjustment and a greater likelihood of early initiation of tobacco use," said Cornelius.
These findings have important implications if supported by further research, since approximately 20 percent of pregnant women smoke, according to Cornelius and colleagues.
The research was supported by grants from the National Institute on Drug Abuse and the National Institute on Alcohol Abuse and Alcoholism.
Nicotine & Tobacco Research is the official peer-reviewed quarterly journal of the Society for Research on Nicotine and Tobacco. For information about the journal, contact Gary E. Swan, PhD, at 650-859-5322.
Posted by the Center for the Advancement of Health, http://www.cfah.org. For information about the Center, call Petrina Chong, pchong@cfah.org, 202-387-2829.
Journal
Nicotine & Tobacco Research