Conceptualizing Problematic Marijuana Use among Marijuana-Using Young Adults: One Size Does Not Fit All

Background: Traditional measures of marijuana problems or dependence may not correctly distinguish problematic from non-problematic use or work consistently across populations of marijuana users with varying levels of tolerance.  The current study examines associations between traditional measures of problematic use (e.g., frequency/quantity, standardized measure of dependence), as well as social norms about use and daily functioning to attempt to better understand and characterize problematic marijuana use among young adult medical marijuana patients (MMP) and non-patients users (NPU). Method:  301 (aged 18-26) current marijuana-using young adults –187 MMP and 114 NPU- were recruited in Los Angeles in 2014-15.   Participants reported recent (90-day) marijuana use patterns and practices, and psychosocial measures, including the Severity of Dependence Scale (SDS).  Subgroup differences between MMP and NPU were examined.  Results:  Those identified by the SDS as “problematic users” reported greater frequency of use (i.e., more days), spent more money on marijuana, and perceived their use to be above social norms relative to other young adults and friends.  However, these factors did not predict dysfunctions across different domains like work, school, and social relationships.  While MMP were more likely to perceive their use to be above social norms relative to other young adults, friends, and peers who use, and MMP were more frequent users than NPU, there were no significant differences in SDS and daily functioning scores between MMP and NPU.  Conclusions:  Findings highlight the complexity in determining problematic use in a heterogeneous marijuana-using young adult population.  More nuanced approaches to distinguish between different problematic and non-problematic use patterns and users are needed.