ADHD News & Research

Smoke Exposure Linked to Increased Rates of Childhood ADHD

A new study finds that secondhand smoke is associated with a higher likelihood of childhood mental disorders. Is this a risk factor for developing ADHD?

The Centers for Disease Control and Prevention says that two out of every five children in the United States are exposed to secondhand smoke on a regular basis. Now, a new study from Spain shows an association between breathing tobacco smoke at home and rates of ADHD in childhood. What might this mean for the health of children in the U.S., and around the world?

The researchers are careful to say that the study does not prove causation. The article, published in Tobacco Control, analyzed data from the 2011-2012 Spanish National Health Interview Survey. This study asked 2,357 parents how long and how often their children, ages 4 to 12, were exposed to secondhand smoke each day. The results showed that 7 percent of children experienced less than one hour of smoke daily, while 4.5 percent were exposed to smoke for more than an hour daily.

Then, the survey asked parents to complete a questionnaire about their child’s mental health. This evaluation found that approximately 8 percent of all kids had a mental disorder. Children who were exposed to smoke for more than an hour daily were more likely to have a mental disorder.

Children who were exposed to smoke for less than one hour daily were twice as likely to have ADHD than were kids who had no smoke exposure at home. Children who were exposed to smoke for more than an hour daily were over three times as likely to have ADHD. The strongest link between smoke and mental health was found with ADHD.

Experts agree that no amount of smoke exposure is healthy for children, and that to avoid a number of health problems, parents should not smoke around kids. While the effects of smoke on physical wellbeing are well-documented, the research on how it impacts cognitive and behavioral health is more limited. Perhaps these new findings will drive more research to determine precisely how smoke and ADHD are related.