Study register · detailSystematic Review · Opioid Reduction · 2020
Medical cannabis for the reduction of opioid dosage in the treatment of non-cancer chronic pain: a systematic review
Okusanya et al.·Systematic ReviewsImpact 5.0
MixedGRADEHigh73 citations
Samplek = 9 Studien n = 7.222 Pat.
DurationUnclear
ControlOpioids without medical cannabis
EndpointOpioid dose reduction
Blindingunklar
DesignSystematic Review
Cannabinoidvollspektrum
”Key finding
Nine studies showed a 64-75% reduction in opioid dosage in combination with medical cannabis, but all studies had high risk of bias and a causal statement is not possible; the authors warn against generalizations.
Summary
Systematic review on medical cannabis as adjuvant for opioid dose reduction in non-oncological chronic pain; k=9 studies (n=7.222). Opioid dose reduction 64–75% with combination with MC; 32–59,3% of patients used MC for opioid substitution. Slight reduction in hospital admissions (p=0,53) and emergency department visits (p=0,39). High risk of bias in all included studies.
P
PopulationAdults with non-cancer-related chronic pain under opioid therapy, pooled n=7222
I
InterventionMedical cannabis (MC) as adjuvant to opioids
C
ControlOpioids without medical cannabis
O
Outcome64–75% reduction in opioid dose under combined MC/opioid therapy; 32–59,3% of patients used MC as opioid substitute; all included studies with high risk of bias
Confidence in the evidence
Very lowLowModerateHigh
High
The highest of four GRADE levels, the effect estimate is very reliable.
Background: Medical cannabis (MC) is currently being used as an adjunct to opiates given its analgesic effects and potential to reduce opiate addiction. This review assessed if MC used in combination with opioids to treat non-cancer chronic pain would reduce opioid dosage.
Methods: Four databases-Ovid (Medline), Psyc-INFO, PubMed, Web of Science, and grey literature-were searched to identify original research that assessed the effects of MC on non-cancer chronic pain in humans. Study eligibility included randomized controlled trials, controlled before-and-after studies, cohort studies, cross-sectional studies, and case reports. All databases were searched for articles published from inception to October 31, 2019. Cochrane's ROBINS-I tool and the AXIS tool were used for risk of bias assessment. PRISMA guidelines were followed in reporting the systematic review.
Results: Nine studies involving 7222 participants were included. There was a 64-75% reduction in opioid dosage when used in combination with MC. Use of MC for opioid substitution was reported by 32-59.3% of patients with non-cancer chronic pain. One study reported a slight decrease in mean hospital admissions in the past calendar year (P = .53) and decreased mean emergency department visits in the past calendar year (P = .39) for patients who received MC as an adjunct to opioids in the treatment of non-cancer chronic pain compared to those who did not receive MC. All included studies had high risk of bias, which was mainly due to their methods.
Conclusions: While this review indicated the likelihood of reducing opioid dosage when used in combination with MC, we cannot make a causal inference. Although medical cannabis' recognized analgesic properties make it a viable option to achieve opioid dosage reduction, the evidence from this review cannot be relied upon to promote MC as an adjunct to opioids in treating non-cancer chronic pain. More so, the optimal MC dosage to achieve opioid dosage reduction remains unknown. Therefore, more research is needed to elucidate whether MC used in combination with opioids in the treatment of non-cancer chronic pain is associated with health consequences that are yet unknown.
Systematic Review Registration: This systematic review was not registered.