Girls too young to vote are shaking up global research on smoking.

A worldwide survey of students aged 13-15 has found that the gap between the number of girls and boys that age who were current cigarette smokers was much smaller than expected.

The Global Youth Tobacco Survey, conducted by the Centers for Disease Control's Charles Warren, PhD, and colleagues found that overall, 10.5 percent of boys were current smokers and 6.7 percent of girls were current smokers.

Warren’s team had expected more boys than girls to smoke, but they had expected a much larger gap. Men and women have a bigger gap in smoking than boys and girls, the study shows.

If those teens keep smoking at the same rate as they age, there could be “important implications for the global burden of chronic diseases,” the researchers state in The Lancet.

The findings are “troubling,” write Warren and colleagues. They call for a “redoubling of efforts” to prevent or stop young people from using tobacco products.

Tobacco Goes Young and Global

The Global Youth Tobacco Survey was conducted at 395 sites in 131 countries. The surveys were tailored to each country, translated into local languages, and given out anonymously at schools.

Topics included current cigarette smoking and use of other tobacco products including snuff, chewing tobacco, cigars, pipes, and cigarillos. Among the findings:

--Nearly 9 percent of students were current smokers.

--More than one in 10 students used tobacco products other than cigarettes.

Regional results include:

--The Americas and Europe had the highest percentage of current smokers (nearly 18 percent of students in each region)

--Southeast Asia and the eastern Mediterranean region had the highest percentage of students using tobacco products other than cigarettes (about 13 percent of students in each region).

--The Americas had the highest rate of current use of any tobacco product, including cigarettes (22 percent of students).

Countries that haven’t completed the study include Australia, Canada, Japan, New Zealand, and most of western Europe, the researchers note.

Secondhand Smoke Common

Many students had been exposed to secondhand smoke in the previous week, the study shows.

“More than 30 percent of students in every region of the world were exposed to secondhand smoke at home, and more than 45 percent in every region were exposed to secondhand smoke in public places,” write Warren and colleagues.

European students were most likely to have been exposed to secondhand smoke, at home and in public. Exposure to secondhand smoke was common among teenaged smokers.

“Among students who currently smoked, more than 60 percent in all regions were exposed to smoke at home and more than 70 percent in all regions were exposed to smoke in public,” the researchers write.

Tempted to Try Smoking

Many people start smoking at a young age. The surveys tried to identify nonsmoking students who might start smoking in the next year.

First, students were asked, “If one of your best friends offered you a cigarette, would you smoke it?” Those who said, “No,” were then asked, “At any time in the next 12 months do you think you will smoke a cigarette?”

Nearly one in five students (18 percent) who had never smoked cigarettes reported being susceptible to smoking during the coming year, the researchers write. That vulnerability was stronger in boys than girls and strongest in Europe and the Americas, the study shows.

By Miranda Hitti, reviewed by Louise Chang, MD

SOURCES: Warren, C. The Lancet, Feb. 17, 2006; online edition. News release, The Lancet.