Both LGBQ sexual identity and traumatic experiences in childhood are linked to a heightened risk of suicidal thoughts and behaviors, U.S. researchers say.

Teens who identify as lesbian, gay, bisexual or are questioning their sexual identity are also more likely than their heterosexual peers to have had adverse childhood experiences (ACEs) in childhood, the study team reports in Journal of Adolescent Health.

Suicide is the second leading cause of death among adolescents and young adults, and there is evidence that suicide rates are increasing in this age group, they write.

“It is imperative that we identify adolescent populations at greatest risk to guide our prevention efforts,” lead author Kristen Clements-Nolle, of the School of Community Health Sciences of the University of Nevada, Reno, told Reuters Health by email.

“Furthermore, cumulative exposure to ACEs greatly increased suicide risk behaviors among sexual minority adolescents. For example, compared with heterosexual students with no exposure to ACEs, LGB/not sure students with two or more ACEs had approximately 13 times higher odds of attempting suicide in the past year,” Clements-Nolle said.

To examine the relationships among teen sexual identity, childhood trauma and suicide risk, Clements-Nolle and colleagues enrolled approximately 5,000 students from 97 high schools in Nevada to fill out questionnaires and answer questions about their sexual identity and exposure to adverse childhood experiences.

Adverse childhood events included such things as being physically forced to have sex with someone, or being beaten, kicked or physically hurt by an adult. In addition, students were asked about their exposure to domestic violence, mental illness and substance abuse by family members.

Participants were also asked if they had ever seriously considered suicide during the past year and how many times had they attempted suicide during that time.

About 10 percent of students self-identified as lesbian, gay or bisexual (LGB), and nearly 5 percent were not sure of their sexual identity. Just over 85 percent of students identified as heterosexual.

The LGB and questioning students were more likely to be exposed to adverse childhood events. More than half of LGB and 40 percent of questioning students reported at least two ACEs, compared to about one-quarter of heterosexual students reporting the same exposure.

For all students, the greater the number of adverse experiences they reported, the greater was their risk of having had suicidal thoughts during the past year.

Sexual identity was also linked to risk of suicidal thinking. Compared with heterosexual students with no ACEs, LGB and questioning students overall were three times more likely to report suicidal thoughts.

LGB and questioning students who reported one ACE were almost 7 times more likely to think about suicide compared to heterosexual students with one ACE. With three or more ACEs, LGB and questioning students were 14 times more likely to think about suicide compared to heterosexual counterparts.

Compared to heterosexual students with no ACEs, LGB and unsure students were almost 4 times more likely to have attempted suicide.

“Studies have shown that family acceptance and parental caring may reduce suicidal behaviors among LGB adolescents and young adults,” Clements-Nolle said.

Future research should evaluate whether interventions that support families with sexual minority youth and promote acceptance of adolescent sexual identity can also impact childhood victimization and household dysfunction, said Clements-Nolle.

“While the assessment of intervention effectiveness was beyond the scope of the current study, the higher prevalence of ACEs among adolescents who are LGB or are not sure of their sexual identity and the demonstrated inﬂuence on suicide risk behaviors highlight the need to ensure that suicide prevention efforts for sexual minority youth are trauma-informed,” Clements-Nolle said.

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