If mom or dad is a smoker, their teenager is more likely to be a smoker too

Researchers used data between 2004 and 2012 from the National Survey on Drug Use and Health, which interviewed annually more than 67,000 persons over the age of 12. The study itself focused on 35,000 parent-adolescent pairs and analyzed their responses regarding the smoking status and nicotine dependence of parents and adolescents. Additional data were collected, including parent and adolescent perceived risk of smoking, depression, adolescent use of alcohol or other drugs, and perceptions of the quality of parenting, such as parental monitoring, level of support, and instances of conflict.

The authors found that 13 percent of adolescents whose parent never smoked said they had ever smoked at least one cigarette. By comparison, 38 percent of teens whose parent was dependent on nicotine had smoked at least one cigarette. Among teenagers who had smoked at least one cigarette, 5 percent were dependent if their parent never smoked, but 15 percent were dependent if their parent was dependent. The effect of parental smoking and dependence persisted after controlling for factors such as adolescent use of alcohol and other drugs. Overall, teens had three times the odds of smoking at least one cigarette, and nearly twice the odds of nicotine dependence, if their parent was dependent on nicotine.

Daughters were almost four times as likely to be dependent on nicotine when their mothers were dependent on nicotine but were not affected by fathers' nicotine dependence. Sons' dependence was not affected by parental dependence.

A number of other factors increased the risk of adolescent lifetime smoking and nicotine dependence, including parent education, marital status, quality of parenting, and adolescent beliefs about the risk of smoking, perceptions of schoolmates' smoking, marijuana use, and mental health. The researchers did not look at the effects of both parents being smokers, smoking by siblings or close friends, community norms, or exposure to pro-tobacco advertising.

What accounts for the strong parental influence as it relates to adolescent smoking? The fact that adolescent smoking was more strongly affected by parents who were current smokers than by parents who had quit, the authors write, suggests a role-modeling effect. In other words, teens imitate their parents. But since former parental smoking did not eliminate risk, other aspects of the family environment or genetic factors probably play a role. The specific effect of parental dependence on adolescent dependence suggests that genetic factors may be more important for the intergenerational transmission of heavy smoking and dependence than for smoking onset.

"Most smokers start smoking when they are teenagers. As this study shows, parents are a powerful influence," says lead author Denise Kandel, PhD, Professor of Sociomedical Sciences in Psychiatry at Columbia University Medical Center and the Mailman School of Public Health, and Research Scientist at the New York State Psychiatric Institute. "To prevent teens from starting to smoke and becoming addicted to tobacco, we need to do a better job of helping parents quit smoking." One way of doing this, she adds, is by reaching out to parents during pediatric visits. This might be a promising strategy because intervention would occur early in a child's life and would reduce the incidence of early smoking onset, which is related to sustained smoking and addiction.