Divergence in cannabis and alcohol use disorder prevalence trends from 2002 to 2019.

INTRODUCTION

Despite increases in the availability, potency, and consumption of cannabis, epidemiological data suggest decreases in the prevalence of cannabis use disorder (CUD) in some groups. Understanding mechanisms for these changes may help improve diagnostic tools for identifying disordered use. This analysis evaluates changes in CUD compared to a substance with comparably stable social and environmental context (alcohol use disorder [AUD]) as well as treatment engagement and need from 2002 to 2019.

METHODS

Data were from the National Survey on Drug Use and Health. Outcomes included CUD and AUD symptoms, treatment engagement, and perceived need. Temporal trends and average annual rate of change [AARC] were computed.

RESULTS

Between 2002 and 2019, daily cannabis use prevalence increased by 94 % (AARC=11.68 %), whereas CUD prevalence among those using cannabis daily reduced by 47.9 % (AARC=-10.30 %). Daily alcohol use prevalence decreased by 10.86 % (AARC=-1.90 %), and AUD prevalence among those using alcohol daily reduced by 3.9 % (AARC=-0.67 %). Prevalence of individual 12-month CUD criteria among those using cannabis daily decreased (-13.4 to -59.6 % change; AARC = -2.4 % to -14 %). Among those using cannabis daily, trends in prevalence of individual AUD criteria varied, with some criteria increasing in prevalence and others decreasing (-30.2-24.6 % change; AARC = -5.82-3.7 %). Treatment engagement and perceived need decreased for cannabis, whereas treatment engagement increased and perceived need decreased for alcohol.

CONCLUSION

These results suggest that CUD and AUD criteria may be determined within the cultural context dictating the definition of harm which has changed for cannabis, but not alcohol, from 2002 to 2019.