Gay, lesbian and bisexual high school students are more likely than heterosexual students to engage in such risky behaviour as smoking, drinking alcohol and carrying guns, a Centres for Disease Control and Prevention study found.
"This report should be a wake-up call for families, schools and communities that we need to do a much better job of supporting these young people," said Howell Wechsler, director of the CDC's Division of Adolescent and School Heath.
"We are very concerned that these students face such dramatic disparities for so many different health risks."
The study, which surveyed 156,000 high school students is the largest of its kind by the federal government.
Researchers analysed data from student surveys conducted from 2001-2009 in Connecticut, Delaware, Maine, Massachusetts, Rhode Island, Vermont and Wisconsin, and also in the Boston, Chicago, Milwaukee, New York City, San Diego and San Francisco school districts.
When asked if they had driven a car while drinking alcohol within the last 30 days, 15.4% of gay and lesbian students responded "yes," compared to 7.8% of heterosexual students.
The gap was even greater on whether students had carried a gun at least one day during the previous month. About 12% of gay and lesbian students said they had carried a gun, almost four times more than heterosexual students.
There also was a large disparity with cigarette smoking, with 27.8% of gay and lesbian students reporting they had smoked more than 10 cigarettes in a day during the previous month compared to 9.1% of heterosexual students.
Gay and lesbian students were much more likely to have seriously contemplated suicide, the study found. Nearly 30% of those students said they had considered suicide compared to 11.7% of heterosexual students.
The study results quantify what advocates say they have long known anecdotally.
Gay, lesbian and bisexual youths are often driven to risky behaviour because they are rejected by their families and other support groups, said Laura McGinnis, spokeswoman for the Trevor Project, a national organisation that provides crisis counselling and suicide prevention programmes for youths.
"We've known this for years but the research hasn't been there to back it up," she said.
She said the new data should help increase the awareness of policymakers and lead to more training for school staff members.
Wechsler said efforts to promote adolescent health and safety should take into account the "additional stressors these youth experience because of their sexual orientation, such as stigma, discrimination, and victimisation." (Reuters Health)
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