Ehrenreich Heidi, Nahapetyan Lusine, Orpinas Pamela, Song Xiao
Division of Violence Prevention, National Center for Injury Prevention and Control, CDC, 4770 Buford Highway, NE, Atlanta, GA, 30341, USA,
J Youth Adolesc. 2015 Oct;44(10):1929-40. doi: 10.1007/s10964-014-0216-6. Epub 2014 Nov 7.
Rising marijuana use and its lowered perceived risk among adolescents highlight the importance of examining patterns of marijuana use over time. This study identified trajectories of marijuana use among adolescents followed from middle through high school, characterized these by co-occurring problem behaviors and teacher-rated academic skills (study skills, attention problems, and learning problems), and tested sixth-grade predictors of trajectory membership. The sample consisted of a randomly-selected cohort of 619 students assessed annually from sixth to twelfth grade. Using group-based modeling, we identified four trajectories of marijuana use: Abstainer (65.6%), Sporadic (13.9%), Experimental (11.5%), and Increasing (9.0%). Compared to Abstainers, students in the Sporadic, Experimental and Increasing trajectories reported significantly more co-occurring problem behaviors of alcohol use, cigarette smoking, and physical aggression. Sporadic and Experimental users reported significantly less smoking and physical aggression, but not alcohol use, than Increasing users. Teachers consistently rated Abstainers as having better study skills and less attention and learning problems than the three marijuana use groups. Compared to Abstainers, the odds of dropping out of high school was at least 2.7 times higher for students in the marijuana use trajectories. Dropout rates did not vary significantly between marijuana use groups. In sixth grade, being male, cigarette smoking, physical aggression and attention problems increased the odds of being in the marijuana use trajectories. Multiple indicators--student self-reports, teacher ratings and high school dropout records--showed that marijuana was not an isolated or benign event in the life of adolescents but part of an overall problem behavior syndrome.
青少年中使用大麻的情况不断增加及其感知风险的降低凸显了研究大麻使用模式随时间变化的重要性。本研究确定了从初中到高中阶段青少年大麻使用的轨迹，通过同时出现的问题行为和教师评定的学术技能（学习技能、注意力问题和学习问题）对这些轨迹进行特征描述，并测试了六年级时轨迹归属的预测因素。样本包括从六年级到十二年级每年接受评估的619名随机抽取的学生队列。使用基于群体的建模方法，我们确定了大麻使用的四种轨迹： Abstainer（65.6%）、Sporadic（13.9%）、Experimental（11.5%）和Increasing（9.0%）。与 Abstainer轨迹的学生相比，Sporadic、Experimental和Increasing轨迹的学生报告同时出现的酒精使用、吸烟和身体攻击等问题行为显著更多。Sporadic和Experimental轨迹的使用者报告的吸烟和身体攻击行为显著少于Increasing轨迹的使用者，但酒精使用情况并非如此。教师一直认为 Abstainer轨迹的学生比三个大麻使用轨迹的学生具有更好的学习技能，注意力和学习问题更少。与 Abstainer轨迹的学生相比，大麻使用轨迹的学生高中辍学的几率至少高出2.7倍。大麻使用轨迹组之间的辍学率没有显著差异。在六年级时，男性、吸烟、身体攻击和注意力问题会增加处于大麻使用轨迹的几率。多种指标——学生自我报告、教师评定和高中辍学记录——表明，大麻在青少年生活中并非孤立或良性事件，而是整体问题行为综合征的一部分。
