Adding to previous findings that teens with mental health disorders are more likely than their peers to engage in high-risk sexual behaviors, such as unprotected sex, new study results from Bradley Hasbro Children's Research Center show that an additional risk is associated with some psychiatric diagnoses.

Specifically, teens who experience the manic phase of bipolar disorder are more sexually active, have more partners, and are more likely to have sexually transmitted infections (STIs) than their peers, wrote the authors in the Journal of Consulting and Clinical Psychology. Also, teens with externalizing disorders—ADHD, conduct disorders, angry behaviors, defiant behaviors, or hostile behaviors—are more likely than their peers to be sexually active, remaining true even when they have a co-existing internalizing disorder like anxiety, depression, of PTSD.

"Increased sexual risk taking may be linked to these disorders because they're often associated with impulsive or reckless behaviors, which could include multiple sexual partners or not using condoms regularly," said lead author Larry K. Brown, MD, Bradley Hasbro Children's Research Center, and professor of psychiatry and human behavior, The Warren Alpert Medical School, Brown University. "Because of their increased vulnerability to HIV and other sexually transmitted infections, the sexual risk behavior of teens with these diagnoses should be carefully and routinely screened as part of their mental health treatment."

For the study, 840 teens and their parents from Providence, RI, Atlanta, GA, and Chicago, IL, who participated in Project Style (Strengthening Today's Youth Life Experience)—an HIV prevention program for parents and youth with significant mental health disorders—completed computer-assisted surveys for obtaining information about their psychiatric symptoms and sexual behaviors. Teen participants completed urine screens to test for STIs.

Of 153 teens with a mania diagnosis, 48 with internalizing disorders, 282 with externalizing disorders, 252 with more than one diagnosis, and 105 who received mental health treatment but did not meet criteria for any of the assessed psychiatric diagnoses—at an average age of 15 years—more than one-half reported a history of vaginal or anal intercourse. Of those who were sexually active, 31% had been so in the previous 90 days with an average of two partners, 29% did not use a condom during their most recent encounter, 15% reported four or more partners, and 14% tested positive for an STI.

Although teen participants with an externalizing disorder tended to engage in risky sexual behavior, those with mania were at an even higher risk for HIV and STI (four times that of other groups), likely due to their likelihood to have significantly more sexual partners.

"This is interesting because there's very little information on adolescents with mania," said Brown, who is also a professor of psychiatry and human behavior at The Warren Alpert Medical School of Brown University. "We know that adults with mania are more likely to engage in risky sexual behavior, but we haven't had data like this before for teens."