Risky Behaviors Are Symptoms That Require Screening, Study Says

Chapel Hill, NC – New research shows that when teen-age boys and girls experiment with sex, drugs and alcohol, girls are at much greater risk of depression than boys.

The study from PIRE Chapel Hill Center found that if girls and boys abstain from these behaviors, their risk for depression doesn't significantly differ, which is contrary to the widely-held assumption that girls are more prone to depression than boys. However, as soon as they both start experimenting, even only occasionally, girls become more depressed than boys, according to the study published this month. At higher levels of substance abuse and sexual activity among teens, boys and girls show similar levels of depressive symptoms.

While all teens engaging in higher levels of alcohol and drug use and sexual activity should be screened for depression, girls, in particular, should be screened even if they are only experimenting, said Martha Waller, Ph.D., the study's primary investigator.

"What's interesting is that just being female does not necessarily put you at a greater risk for depression, which has generally been assumed," she said. "At puberty, we see that the prevalence of depression starts to greatly increase in girls but not in boys, and this gender difference has always been attributed to developmental changes in girls such as hormonal changes. But in this study, we find that for girls who have not experimented with smoking or drinking or become sexually active, their risk for depression is no greater than males, regardless of their developmental status."

Published this month in Archives of Women's Mental Health, the study of nearly 20,000 teens showed that girls who used alcohol, tobacco and drugs only occasionally are 2½  times as likely to show signs of depression as teen girls who abstained. When girls experiment with sex, they are 3½ times as likely to experience depressive symptoms as those who abstain, according to the research, which was funded by the National Institute on Drug Abuse.

While girls experience significantly more depressive symptoms than boys at low levels of alcohol and drug use and sexual activity, boys who engage in these risk behaviors still experience more depressive symptoms than those who abstain. For both girls and boys, the depressive symptoms generally increased as risk behavior increased. Girls who used marijuana regularly were almost nine times as likely to experience depression, and those who used IV drugs were nearly 18 times as likely to suffer from depression compared to girls who did not, the study found. Boys who binge drink are about 2½ times as likely to be depressed, while those who regularly use marijuana are five times as likely, and those who use intravenous drugs are six times as likely, to show symptoms of depression compared to boys who abstain completely.

Both substance abuse and sexual activity may alter a girl's social context, which could induce stress and change self-perceptions, both of which could contribute to depression, Waller said. In addition, there may be differences in how girls and boys physically respond to substance use that help explain the sex differences, she said.

Other research last year from PIRE Chapel Hill Center showed that sex, drugs and alcohol among teens actually precede – and apparently lead to -- the onset of adolescent depression, which contradicts the common belief that depressed teens may be "self-medicating" through substance abuse and sex.

PIRE, or Pacific Institute for Research and Evaluation, is a national nonprofit public health research institute with centers in eight U.S. cities that is supported primarily by federal and state research and program funds.

For more information, to set up an interview with the researcher or to obtain a copy of the published report, contact Michelle Blackston at (301) 755-2444 or mblackston@pire.org.