Cannabis use, pain and prescription opioid use in people living with chronic non-cancer pain: Findings from a four-year prospective cohort

Abstract

Background:

There has been growing interest in the use of cannabis and cannabinoids to treat chronic non-cancer pain (CNCP). Cannabis and cannabinoids have attracted attention because of their greater safety compared with opioids, and the possibility that their use can reduce opioid dose requirements via an opioid-sparing effect. Both factors have been proposed to contribute to fewer opioid-related deaths.

Methods:

We used The Pain and Opioids IN Treatment (POINT) study, a national cohort of 1,514 people living with CNCP prescribed opioids, to examine relationships between cannabis use, opioid use and pain outcomes over four years.

Outcomes:

Cannabis use was common, and by four-year follow-up, 24.3% had used cannabis for pain. Interest in using cannabis for pain doubled from 33% (baseline) to 60% (four years). We found that patients who had used cannabis had greater pain severity and interference, lower pain self-efficacy, and greater GAD severity than patients who had not used cannabis. We found no evidence of a temporal relationship between cannabis use and pain severity or pain interference, and no evidence that cannabis use reduced prescribed opioid use or increased rates of opioid discontinuation.

Interpretation:

Cannabis use was common in people living with CNCP prescribed opioids, but we found no evidence that cannabis use improved patient outcomes. Those who used cannabis had greater pain and lower self-efficacy in managing pain and there was no evidence that cannabis use reduced pain severity or interference or exerted an opioid-sparing effect.