The Association Between Cannabis Use and Aberrant Behaviors During Chronic Opioid Therapy for Chronic Pain.

Objective: Health care providers are likely to see an increase in the concomitant use of cannabis and opioids, particularly with the increased liberalization and ongoing research into the possible role of medical marijuana for chronic pain. Recent literature reports a prevalence of concurrent use ranging from 8.9% to 31.8%. The primary aim of this study was to determine the relationship between cannabis use and aberrant drug behaviors in noncancer pain patients receiving chronic opioid therapy. Design: Retrospective chart review. Setting: Community-based, interdisciplinary pain management center. Subjects: Data from 209 patients who were evaluated for a medication management program between October 1, 2011, and January 1, 2014, and met inclusion criteria. Forty-four were positive for cannabis in their initial random urine drug toxicology.
Methods: Data from electronic health records, including demographics, urine drug toxicology, disability, opioid dose, opioid risk assessment data, and pain severity were analyzed to examine differences among cannabis users and noncannabis users.
Results: Subjects with cannabis in their initial urine drug toxicology were more likely to have a future occurrence of an opioid-related aberrancy (P < 0.001), be male (P = 0.047), have a history of substance abuse (P = 0.013), and be enrolled into a higher level of clinical monitoring of opioid medication use (P = 0.008). No other associations with demographic and clinical variables reached statistical significance. Conclusions: Concurrent use of cannabis and opioids by patients with chronic pain appears to indicate higher risk for opioid misuse. Closer monitoring for opioid-related aberrancy is indicated for this group of patients.