States that legalized same-sex marriage before it became federal law two years ago saw a sharp decline in suicide attempts by high school students, according to an analysis by researchers at the Johns Hopkins Bloomberg School of Public Health.
The researchers compared the suicide rates of 32 states that passed the laws with states that didn't implement the policies. They found a 7 percent drop, or 134,000 fewer suicide attempts per year, in states with same-sex marriage laws, while those without them saw little change in suicide attempts.
The results were published Monday in the journal JAMA Pediatrics.
The data offers a glimpse into the way public policy can affect health outcomes, said Julia Raifman, the study's lead author and a postdoctoral fellow in the department of epidemiology at the Bloomberg School. The largest declines in suicide attempts were among those teens who identified as lesbian, gay, bisexual or transgender.
"I think it is good for parents, teachers and medical professionals to be aware of the disparity and try to address it," Raifman said.
The study did not look at why the laws resulted in reduced suicide rates, but Raifman said that the acceptance of same-sex marriages may make teens feel less stigmatized because of their sexual orientation.
The study compared states that had adopted same-sex marriage laws through January 2015 to states that did not enact state-level legalization. The Supreme Court made its landmark decision in June 2015, ruling that the Constitution guaranteed same-sex couples the right to marry.
Researchers analyzed data from the Youth Risk Behavior Surveillance System, a survey conducted by the Centers for Disease Control and Prevention that collects data on types of risky health behaviors that contribute to the leading causes of death and disability among youth and adults.
The data included 32 of the 35 states that enacted same-sex marriage policies between Jan. 1, 2004, and Jan. 1, 2015. The researchers also analyzed data from Jan. 1, 1999, to Dec. 31, 2015, to look at suicide attempts five years before the first same-sex marriage policy went into effect in Massachusetts.
Suicide is the second-most-common cause of death among people ages 15 to 24 in the United States behind unintentional injury, according to the CDC.
Raifman said the research could be used to meet federal goals to reduce teen suicide rates. Healthy People 2020, a program run by the U.S. Department of Health and Human Services, has a goal of reducing adolescent suicide rates by 10 percent by 2020. She said there needs to be more large-scale programs aimed at reducing suicide among teens who identify as gay, lesbian or bisexual.
"I think there is a need for further research," Raifman said. "A lot of studies look at interventions for suicide attempts, but none have really focused on LGBT interventions."