Adopted children may be more likely than their non-adopted siblings to attempt suicide, according to a new U.S. study.
Researchers urged doctors to be on the lookout for signs of trouble in adopted teen patients but said parents should not be overly alarmed by the results.
"While our findings suggest that adoptees may have an elevated risk for suicide attempt, the majority of the adopted individuals in our study were psychologically well-adjusted," lead author Margaret Keyes, a psychologist at the University of Minnesota in Minneapolis, said.
Suicide is the third leading cause of death for young people between the ages of 10 and 24 years old, according to the Centers for Disease Control and Prevention. According to the agency, 4,600 youth deaths each year in the U.S. are suicides, and a much larger number of young people make attempts to take their own lives.
Previous research in Sweden found that adopted kids in that country were more likely to attempt suicide than nonadopted kids, but no comparable study had been done in the U.S., according to Keyes and her coauthors writing in the journal Pediatrics.
They examined data from an existing University of Minnesota study of 692 adopted children and 540 nonadopted siblings in Minnesota.
All of the adopted kids, who were between 11 and 21 years old during the study period, had been taken in by their families before age two and had a biologically unrelated teenage sibling in the same home.
Almost three quarters of the adopted children were born abroad, most of the foreign-born children were from South Korea and 60 percent of those were girls.
At the beginning of the study, and again about three years later, the researchers asked participating parents and kids if either of the children had made a suicide attempt.
Over the three years of the study, 56 children attempted suicide at least once, according to the family members' reports. Of those kids, 47 were adopted and nine were not adopted.
When previous self-harm behavior was taken into account, researchers calculated that adopted teens were 3.7 times more likely to attempt suicide than the other teens.
When the researchers adjusted for other factors often linked with suicidal thinking or behavior, including drug use, depression, academic struggles and personality traits like alienation and impulsivity, the increased risk for adopted kids remained.
Although this study could not determine why the adopted teens were more likely to attempt suicide, the authors note that other research has suggested burdens carried by adopted children that may be contributing factors.
In the Swedish study, for example, researchers showed that substance abuse, suicidal behavior and mental illness among the biological parents of domestically adopted kids could explain about one third of the children's increased risk for suicide.
For children adopted from abroad, Keyes' team writes, there is also the possibility that loss of cultural identity and experience of ethnic discrimination only add to the pressures on a child.
"Other mediating factors, not considered in our study, may include: heritable risk, prenatal factors, factors unique to relinquishment by a biological parent, early trauma, weak attachment to adoptive families and loss of cultural identity and ethnic discrimination," Keyes told Reuters Health by email.
Two of those factors may be most critical in determining suicide risk, according to Ritch C. Savin-Williams, a professor of developmental psychology at Cornell University in Ithaca, namely: genetics and early trauma.
"Many of us believe that these two might well be the most important distinguishing factors separating the two groups, answering the question of why were these babies put up for adoption in the first place," he told Reuters Health.
The small size of the study and limited ethnic diversity make these results not generalizable to the whole of the United States, Savin-Williams said.
The study was also limited to self-reported suicide attempts and did not distinguish between types of attempts, some of which can be far more serious and worrisome than others, Savin-Williams noted.
"We do not believe that adoptive parents should be alarmed by these findings," Keyes said.
"However, parents and clinicians may want to be aware of the increased potential for suicide attempt in adopted adolescents who evidence other risks for suicidal behavior," she said.