In a group of 582 US high school students, it was found that those with a lower sense of purpose were more likely to engage in risky behaviours (e.g. drug-taking, driving under the influence of alcohol). This was the finding for males and females, and for the three ethnic groups represented in the sample.
Sayles, M.L. (1995). Adolescents’ purpose in life and engagement in risky behaviours: Differences by gender and ethnicity. Dissertation Abstracts International, 55: 2727.