Risky behavior may foreshadow depression in youngsters

New findings from a study supported by the National Institute on Drug Abuse (NIDA) at the National Institutes of Health show that girls and boys who exhibit a high level of risky behavior have a similar chance of developing symptoms of depression. Gender differences become apparent at low and moderate levels of risky behavior, however, with girls being significantly more likely than boys to experience symptoms of depression. The study, which incorporated data from almost 19,000 teenagers, was published in the May 15, 2006, issue of the Archives of Women's Mental Health.

Martha Waller, MD, of the Pacific Institute for Research and Evaluation, and her colleagues provided new findings from interviews with teenagers that were conducted as part of the National Longitudinal Study of Adolescent Health in 1995. The researchers clustered the teens into 16 groups according to their behaviors, and then correlated those behaviors with symptoms of depression. Groups included abstainers, who refrained from engaging in sexual activity and from using alcohol, tobacco, or other drugs; teens who engaged in low- and moderate-risk behaviors, such as experimenting with substance abuse or sex; and teens who engaged in high-risk behaviors, such as exchanging sex for drugs or money or abuse of intravenous drugs.

"Among abstainers, there were no differences [in symptoms] between girls and boys in their likelihood of having symptoms of depression," said Dr. Waller.

When abstaining girls were compared with risk-taking girls, the researchers observed that any risky activity—no matter how modest in degree—was associated with an increased risk of symptoms of depression. For example, girls who experimented with drugs and girls who experimented with tobacco and alcohol were more than twice as likely to have symptoms of depression as girls who abstained completely.

Among boys, most, but not all, risk profiles were associated with a greater likelihood of such symptoms, compared to abstainers. Boys who drank alcohol and boys who were binge drinkers were about two-and-one-half times as likely to experience symptoms of depression, whereas those who abused intravenous drugs were about six times as likely to have symptoms of depression as boys who abstained completely.

For most of the high-risk behaviors profiled, there were also no significant gender differences in symptoms of depression.

"The burden of illness associated with depression during adolescence is considerable, and psychosocial problems—including substance abuse—are associated with depressive disorders in teens," commented NIDA Director Nora D. Volkow, MD.