Risk of Cannabis Use Disorder in Chronic Pain: Longitudinal Links to Pain Outcomes.

Objectives: The aim of this study was to compare individuals with chronic pain who were cannabis nonusers and those at low, moderate, and high cannabis use disorder (CUD) risk levels on baseline psychosocial and pain-related characteristics, as well as the longitudinal trajectories of pain severity and interference.

Methods: A cohort of 1453 individuals with chronic pain, recruited online, participated in this 2-year longitudinal study, which included baseline, 3-, 12-, and 24-month follow-up surveys. The Cannabis Abuse Screening Test was used to assess CUD risk, and the Brief Pain Inventory was used to assess pain outcomes.

Results: Among participants (65.5% female; 86.1% White), 36.3% reported using cannabis, and 39.8% of cannabis users showed high CUD risk. Compared with nonusers, individuals at higher CUD risk tended to be younger, male, of lower socioeconomic status, and at higher risk of alcohol use disorder. They also reported greater pain severity and interference, more pronounced central sensitization symptoms, and elevated mental health symptoms. However, pain severity and interference trajectory slopes over 2 years were not different among the nonusers versus individuals at varying CUD risk levels.

Conclusions: A significant portion of individuals with chronic pain who use cannabis may be at risk for CUD. Although higher CUD risk was not associated with worsening pain outcomes over 2 years compared to nonusers, its connection to worse mental health and pain symptoms at baseline highlights the need for targeted CUD risk assessments, patient education on CUD risk, and integrated care with mental health support in chronic pain management.