Julia Dratva, MD, MPH, of the Swiss Tropical and Public Health Institute in Basel, Switzerland, and colleagues measured the artery walls of 283 young people in that age group. About 11% said they smoked at least once a week, 15% reported smoking at least once a month, and the rest were nonsmokers.
Compared with the nonsmokers, both the weekly and monthly smokers had thicker artery walls. That's indicative of early atherosclerosis, a buildup of plaque in the artery walls that can restrict blood flow, Dratva says.
Even a Little Smoking Hurts
The link between smoking and thicker artery walls held true even after the researchers took into account other risk factors, such as whether the parents smoked.
"After a relatively short duration of active smoking, the [arteries] already show signs of structural changes," Dratva says.
American Heart Association spokesman Russell Luepker, MD, of the University of Minnesota in Minneapolis, says it's now well-established that heart disease and stroke risk factors in childhood track into adulthood.
"The fact that cigarette smoking is one such risk factor is an important finding. This is another of a thousand reasons why kids shouldn't smoke," he says.
The findings were presented at the annual meeting of the European Society of Cardiology.
Many Teens Smoke
About 45% of U.S. high school students have tried cigarettes, according to the CDC's 2011 National Youth Risk Behavior Survey.
Statistics show that about 9 out of 10 tobacco users start before they're 18 years old.
These findings were presented at a medical conference. They should be considered preliminary, as they have not yet undergone the "peer review" process, in which outside experts scrutinize the data prior to publication in a medical journal.