Study register · detailKlinische Studie · Chronic Pain · 2015
Cannabis for the Management of Pain: Assessment of Safety Study (COMPASS)
Ware et al.·The Journal of PainImpact 1.0
MixedGRADEHigh247 citations
Samplen = 431 Pat.
Duration1 year
ControlControl group
EndpointAdverse events
Blindingoffen
DesignKlinische Studie
Cannabinoidvollspektrum
”Key finding
No increased risk for serious adverse effects, but increased risk for non-serious adverse effects (mostly mild to moderate) under cannabis compared to the control group.
Summary
Prospective cohort study (COMPASS) over 1 year, n=431 (215 cannabis users with chronic non-cancer-related pain, 216 controls). Median daily dose 2.5 g standardised cannabis (12.5% THC). No difference in serious adverse events (adjusted IRR=1.08, 95% CI 0.57–2.04); increased risk for non-serious adverse effects (adjusted IRR=1.73, 95% CI 1.41–2.13), predominantly mild to moderate. No differences in secondary safety parameters (lung function, neurocognition, laboratory).
P
PopulationAdults with chronic non-cancer pain; cannabis group n=215 (141 current, 58 ex-users), control group n=216
I
InterventionStandardised herbal cannabis (12,5% THC), median 2,5 g/day oral/inhaled, over 1 year
C
ControlControl group: patients with chronic pain without current cannabis use from the same clinics
O
OutcomeNo significant difference in serious adverse events (adjusted IRR=1,08; 95% CI 0,57–2,04); increased risk for non-serious adverse events (adjusted IRR=1,73; 95% CI 1,41–2,13), predominantly mild to moderate
Confidence in the evidence
Very lowLowModerateHigh
High
The highest of four GRADE levels, the effect estimate is very reliable.
Cannabis is widely used as a self-management strategy by patients with a wide range of symptoms and diseases including chronic non-cancer pain. The safety of cannabis use for medical purposes has not been systematically evaluated. We conducted a prospective cohort study to describe safety issues among individuals with chronic non-cancer pain. A standardized herbal cannabis product (12.5% tetrahydrocannabinol) was dispensed to eligible individuals for a 1-year period; controls were individuals with chronic pain from the same clinics who were not cannabis users. The primary outcome consisted of serious adverse events and non-serious adverse events. Secondary safety outcomes included pulmonary and neurocognitive function and standard hematology, biochemistry, renal, liver, and endocrine function. Secondary efficacy parameters included pain and other symptoms, mood, and quality of life. Two hundred and fifteen individuals with chronic pain were recruited to the cannabis group (141 current users and 58 ex-users) and 216 controls (chronic pain but no current cannabis use) from 7 clinics across Canada. The median daily cannabis dose was 2.5 g/d. There was no difference in risk of serious adverse events (adjusted incidence rate ratio = 1.08, 95% confidence interval = .57-2.04) between groups. Medical cannabis users were at increased risk of non-serious adverse events (adjusted incidence rate ratio = 1.73, 95% confidence interval = 1.41-2.13); most were mild to moderate. There were no differences in secondary safety assessments. Quality-controlled herbal cannabis, when used by patients with experience of cannabis use as part of a monitored treatment program over 1 year, appears to have a reasonable safety profile. Longer-term monitoring for functional outcomes is needed.
Study Registration: The study was registered with www.controlled-trials.com (ISRCTN19449752).
Perspective: This study evaluated the safety of cannabis use by patients with chronic pain over 1 year. The study found that there was a higher rate of adverse events among cannabis users compared with controls but not for serious adverse events at an average dose of 2.5 g herbal cannabis per day.