Prevalence and correlates of hashish use in a national sample of high school seniors in the United States (2015)

Background: Cannabis (marijuana) use and acceptance towards use are increasing in the US, and state-level policies are becoming more liberal. A wealth of research has been conducted to examine risk factors for use; however, studies rarely differentiate between different forms of marijuana.
Objective: We sought to determine prevalence of use and delineate who is at risk for use of hashish, a more potent form of marijuana.
Methods: We examined data from a nationally representative sample of high school seniors in the Monitoring the Future study (2007-2011; weighted n = 10 597). We determined how sociodemographic factors and reasons for marijuana use correlated with recent (12 month) hashish use.
Results: Prevalence of recent hashish use was 6.5% and it was used by 18.3% of recent marijuana users. Hashish and other marijuana use tended to share many of the same correlates; however, associations were often stronger for hashish use. Females were consistently at low risk for use and users of other drugs were consistently at high risk for use. Black students tended to be at low risk for hashish use. Low risk of identifying as Hispanic or religious and high risk of higher personal income or going out more evenings per week for fun disappeared when controlling for other drug use. Using marijuana because the student felt he/she was "hooked'' nearly doubled the odds for hashish use.
Conclusions: This was the first national study to examine prevalence and correlates of hashish use. These findings can inform prevention in a time of increasing popularity of marijuana use.