Has occasional cannabis use among adolescents also to be considered as a risk marker?

The association between cannabis use and health or behaviour problems is quite well established. Little is known about the risk markers related to occasional or former use. This work aims to explore associations between well-being in life and different levels of cannabis use.

A total of 16 934 French adolescents completed self-administered multi-choice questionnaires (from the European Study ESPAD 2003) on substance consumption, psychopathology, socio-demographics and schooling. Four groups were defined according to cannabis use: Never-Users (no lifetime consumption and no consumption during the last month), Former Users (at least one lifetime consumption but none in the last month), Current Occasional Users (<5 times during the previous month) and Current Heavy Users (> or =5 times during the previous month). Analyses were performed with SAS 8.2 software and adjusted for gender and age.

A total of 68.2% of students aged 12-19 years were Never-Users, 15.5% Former Users, 8.3% Current Occasional Users and 8.0% Current Heavy Users. When Former Users were compared with Never-Users, significant differences were found with regard to suicide attempt, odds ratio (OR) = 2.9 (2.4-3.4); multiple acts of violence, OR = 6.4 (5.4-7.7) and running away from home, OR = 3.1 (2.5-3.8). These differences were greater when Current Occasional Users were compared with Never-Users: suicide attempt, OR = 4.2 (3.5-5.0); multiple acts of violence, OR = 12.6 (10.2-15.5) and running away from home OR = 4.2 (3.4-5.4). Differences remain even after adjustment for alcohol and tobacco consumption.

These results showed that occasional and even former marijuana use is associated with risky behaviour among adolescents.