Children who are exposed to secondhand smoke are more likely to have mental and behavioral issues and are more likely to smoke later in life, according to two new studies in the August edition of the journal Pediatrics.
About 5 million children in the United States live in homes where they are exposed to secondhand smoke, which puts them at greater risk for asthma, ear infections, and sudden infant death syndrome, according to researchers at the Harvard School of Public Health.
According to the new studies from Harvard and Washington University in St. Louis, children exposed to secondhand smoke more commonly have behavioral and mental-health problems and are more likely to smoke when they grow up than children from non-smoking homes.
Hillel Alpert and colleagues at Harvard found secondhand smoke can increase the odds of developing certain mental- and behavioral-health disorders by up to 50 percent.
Children who were exposed to secondhand smoke were twice as likely to develop neurobehavioral disorders including attention deficit disorder, attention deficit hyperactivity disorder, and learning disabilities, the study found. The findings were based on data from responses of the parents or guardians of more than 55,000 children ages 11 and younger to the Centers for Disease Control and Prevention's 2007 National Survey on Children's Health.
"There is an increasing trend of voluntary smoke-free homes but there are still 5 million children under age 12 that are still exposed to secondhand smoke in the home," Alpert said in a telephone interview. "There is a real strong association between secondhand smoke and neurobehavioral disorders. The study indicated that eight percent of those children had learning disabilities and 6 percent had ADD or ADHD."
The telephone survey results don't prove secondhand smoke exposure actually causes behavioral and mental health problems, but Alpert said there was strong evidence of the association between secondhand-smoke exposure and mental-health disorders.
A study in the April Archives of Pediatric and Adolescent Medicine also found that children and teens who breathe in secondhand smoke are at greater risk of suffering from depression and anxiety.
The other Pediatrics study, conducted by researchers at the Washington University School of Medicine in St. Louis and funded by the National Institutes of Health, found that children who breathe secondhand smoke were more likely to become smokers. Looking at children ages 8 to 13 who lived with at least one smoker, researchers found that kids who found smoking to be “unpleasant or gross” were less likely to pick up smoking later in life.
Some states have attempted to reduce the risk of children's exposure to secondhand smoke. Twenty-five states and the District of Columbia have laws prohibiting smoking in public places like restaurants and worksites. Four states—Arkansas, California, Louisiana, and Maine—have laws prohibiting smoking in a car with a child present.