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Issues: Canada recently introduced a public health-based regulatory framework for non-medical cannabis. This review sought to identify a comprehensive set of indicators to evaluate the public health and safety impact of cannabis regulation in Canada, and to explore the ways in which these indicators may be expected to change in the era of legal non-medical cannabis.Approach: Five scientific databases were searched to compile a list of cannabis-related issues of interest to public health and safety. A set of indicators was developed based on topics and themes that emerged. Preliminary evidence from other jurisdictions in the USA and Canada that have legalised medical and/or non-medical cannabis (e.g. Colorado, Washington) was summarised for each indicator, wherever possible.Key Findings: In total, 28 indicators were identified under five broad themes: public safety; cannabis use trends; other substance use trends; cardiovascular and respiratory health; and mental health and cognition. Preliminary trends from other legalised jurisdictions reveal little consensus regarding the effect of cannabis legalisation on public health and safety harms and an emerging body of evidence to support potential benefits (e.g. reductions in opioid use and overdose).Implications: In addition to indicators of commonly discussed challenges (e.g. cannabis-related hospitalisations, cannabis-impaired driving), this review led to the recommendation of several indicators to monitor for possible public health and safety improvements.Conclusion: In preparing a comprehensive public health and safety monitoring and evaluation system for cannabis regulation, this review underscores the importance of not only measuring the possible risks but also the potential benefits. [ABSTRACT FROM AUTHOR]

Objective To evaluate the association between opioid dosage and ongoing therapy with physical function and disability in patients with neuropathic pain (NeP). Design Secondary analysis of a prospective cohort. Setting Multicenter clinical NeP registry. Subjects Seven hundred eighty-nine patients treated for various NeP diagnoses. Methods The following measures were included: dependent variables. 12-month self-reported physical function (pain disability index [PDI] and medical outcomes study short form-12 physical function [PCSS-12]); independent variables: baseline opioid dose (none, ≤200 mg and >200 mg of morphine equivalent), ongoing opioid use; potential confounding variables: age, sex, baseline pain intensity, and psychological distress (profile of mood states). Analysis of covariance models was created to examine the relationship between opioid therapy and both physical functioning outcomes with adjustment for confounding. Results Complete data was available for 535 patients (68%). Compared with the lower and high dose opioid groups, NeP patients not taking opioids had statistically lower disability and higher physical functioning scores, after adjusting for disease severity. Compared with patients prescribed opioid therapy on an ongoing basis, NeP patients who were not prescribed had statistically lower disability and higher physical functioning scores, after adjusting for disease severity. Improvements in disability and physical functioning scores from baseline and 12-months in all groups were modest and may not be clinically significant. Conclusions Physical functioning and disability did not improve in patients with NeP who were prescribed opioids compared with those who are not prescribed, even after adjusting for disease severity. [ABSTRACT FROM AUTHOR]

Background: There is increasing global awareness and interest in the use of cannabis for therapeutic purposes (CTP). It is clear that health care professionals need to be involved in these decisions, but often lack the education needed to engage in informed discussions with patients. This study was conducted to determine the educational needs of Canadian physicians regarding CTP. Methods: A national needs assessment survey was developed based on previous survey tools. The survey was approved by the Research Ethics Board of the McGill University Health Centre Research Institute and was provided online using LimeSurvey®. Several national physician organizations and medical education organizations informed their members of the survey. The target audience was Canadian physicians. We sought to identify and rank using 5-point Likert scales the most common factors involved in decision making about using CTP in the following categories: knowledge, experience, attitudes, and barriers. Preferred educational approaches and physician demographics were collected. Gap analysis was conducted to determine the magnitude and importance of differences between perceived and desired knowledge on all decision factors. Results: Four hundred and twenty six responses were received, and physician responses were distributed across Canada consistent with national physician distribution. The most desired knowledge concerned "potential risks of using CTP" and "safety, warning signs and precautions for patients using CTP". The largest gap between perceived current and desired knowledge levels was "dosing" and "the development of treatment plans". Conclusions: We have identified several key educational needs among Canadian physicians regarding CTP. These data can be used to develop resources and educational programs to support clinicians in this area, as well as to guide further research to inform these gaps. [ABSTRACT FROM AUTHOR]

Aim Nabilone is a synthetic cannabinoid prescription drug approved in Canada since 1981 to treat chemotherapy-induced nausea and vomiting. In recent years, off-label use of nabilone for chronic pain management has increased, and physicians have begun to express concerns about nabilone becoming a drug of abuse. This study evaluates the evidence for abuse of nabilone, which is currently ill-defined. Study design Scientific literature, popular press and internet databases were searched extensively for evidence of nabilone abuse. Focused interviews with medical professionals and law enforcement agencies across Canada were also conducted. Findings The scientific literature and popular press reviews found very little reference to nabilone abuse. Nabilone is perceived to produce more undesirable side effects, to have a longer onset of action and to be more expensive than smoked cannabis. The internet review revealed rare and isolated instances of recreational use of nabilone. The database review yielded little evidence of nabilone abuse, although nabilone seizures and thefts have occurred in Canada in the past few years, especially in Ontario. Most law enforcement officers reported no instances of nabilone abuse or diversion, and the drug has no known street value. Medical professionals reported that nabilone is not perceived to be a matter of concern with respect to its abuse potential. Conclusions Reports of nabilone abuse are extremely rare. However, follow-up of patients using nabilone for therapeutic purposes is prudent and should include assessment of tolerance and dependence. Prospective studies are also needed to definitively address the issue of nabilone abuse. [ABSTRACT FROM AUTHOR]

The authors argue that Canada should lead in facilitating research on cannabis. Topics include laws on access to herbal cannabis in Canada, the need for clinical data on the therapeutic use of cannabis, and the need for funding of a peer-reviewed cannabis research programme that allows for the procurement of research licenses. The use of funds from the herbal cannabis industry for research is addressed.

Cannabinoids may hold potential for the management of rheumatic pain. Arthritis, often self-reported, is commonly cited as the reason for the use of medicinal herbal cannabis (marijuana). We have examined the prevalence of marijuana use among 1000 consecutive rheumatology patients with a rheumatologist-confirmed diagnosis and compared in an exploratory manner the clinical characteristics of medicinal users and nonusers. Current marijuana use, medicinal or recreational, was reported by 38 patients (3.8%; 95% CI: 2.8-5.2). Ever use of marijuana for medical purposes was reported by 4.3% (95% CI: 3.2-5.7), with 28 (2.8%; 95% CI: 1.9-4.0) reporting current medicinal use. Current medicinal users had a spectrum of rheumatic conditions, with over half diagnosed with osteoarthritis. Medicinal users were younger, more likely unemployed or disabled, and reported poorer global health. Pain report and opioid use was greater for users, but they had similar physician global assessment of disease status compared with nonusers. Medicinal users were more likely previous recreational users, with approximately 40% reporting concurrent recreational use. Therefore, less than 3% of rheumatology patients reported current use of medicinal marijuana. This low rate of use in patients with a rheumatologist-confirmed diagnosis is in stark contrast to the high rates of severe arthritis frequently reported by medicinal marijuana users, especially in Canada. Familiarity with marijuana as a recreational product may explain use for some as disease status was similar for both groups. [ABSTRACT FROM AUTHOR]

Background: Ecological research suggests that increased access to cannabis may facilitate reductions in opioid use and harms, and medical cannabis patients describe the substitution of opioids with cannabis for pain management. However, there is a lack of research using individual-level data to explore this question. We aimed to investigate the longitudinal association between frequency of cannabis use and illicit opioid use among people who use drugs (PWUD) experiencing chronic pain., Methods and Findings: This study included data from people in 2 prospective cohorts of PWUD in Vancouver, Canada, who reported major or persistent pain from June 1, 2014, to December 1, 2017 (n = 1,152). We used descriptive statistics to examine reasons for cannabis use and a multivariable generalized linear mixed-effects model to estimate the relationship between daily (once or more per day) cannabis use and daily illicit opioid use. There were 424 (36.8%) women in the study, and the median age at baseline was 49.3 years (IQR 42.3-54.9). In total, 455 (40%) reported daily illicit opioid use, and 410 (36%) reported daily cannabis use during at least one 6-month follow-up period. The most commonly reported therapeutic reasons for cannabis use were pain (36%), sleep (35%), stress (31%), and nausea (30%). After adjusting for demographic characteristics, substance use, and health-related factors, daily cannabis use was associated with significantly lower odds of daily illicit opioid use (adjusted odds ratio 0.50, 95% CI 0.34-0.74, p < 0.001). Limitations of the study included self-reported measures of substance use and chronic pain, and a lack of data for cannabis preparations, dosages, and modes of administration., Conclusions: We observed an independent negative association between frequent cannabis use and frequent illicit opioid use among PWUD with chronic pain. These findings provide longitudinal observational evidence that cannabis may serve as an adjunct to or substitute for illicit opioid use among PWUD with chronic pain., Competing Interests: I have read the journal's policy and the authors of this manuscript have the following competing interests: M-JM is the Canopy Growth professor of cannabis science at UBC, a position created using unstructured arms’ length gifts to the university from Canopy Growth Corporation and the Government of British Columbia’s Ministry of Mental Health and Addictions. The University of British Columbia has received unstructured funding from NG Biomed, Ltd., an applicant to the Canadian federal government for a license to produce cannabis, to support M-JM. ZW is Coordinating Principal Investigator on a clinical trial sponsored by Tilray, a licensed producer of medical cannabis. ZDC has received research funds and partial salary support from Insys Therapeutics. She has served as a consultant to GB Sciences and Beckley Canopy Therapeutics and is a scientific advisor to FSD Pharma. MAW has consulted for CHI, CannaRoyalty and Zynerba and has received a grant to his institution for clinical research from CanniMed. He was appointed to Chief Medical Officer at Canopy Growth Corp in July 2018 (after the study period ended). He supported the first author in conceptualization of the research, but did not contribute to the study’s methodological design or data analysis. All other authors report no competing interests in relation to the work described.

Unlabelled: 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., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

This prospective observational cohort study addressed the long-term clinical effectiveness of the management of chronic neuropathic noncancer pain at 7 Canadian tertiary pain centers. Patients were treated according to standard guidelines and were followed at 3, 6, 12, 18, and 24 months. Standard outcome measures for pain, mood, quality of life, and overall treatment satisfaction were administered, with the primary outcome measure designated as the composite of 30% reduction in average pain intensity and 1-point decrease in the mean Interference Scale Score (0-10) of the Brief Pain Inventory at 12 months relative to baseline. Of 789 patients recruited, mean age was 53.5 ± 14.2 years (55% female) and mean duration of pain was 4.88 ± 5.82 years. Mean average pain intensity (0-10) at baseline was 6.1 ± 1.9. All standard outcome measures showed statistically significant improvement at 12 months relative to baseline (P < .001). However, only 23.7% attained clinically significant improvement in pain and function at 12 months as the primary outcome measure. Univariable analyses showed poorer outcomes at 12-month follow-up with longer duration of pain (P = .002), greater cigarette use (P = .01), more disability compensation (P = .001), and higher opioid doses at baseline and at 12 months (P < .02). Our present treatment modalities provide significant long-term benefit in only about a quarter of patients with neuropathic pain managed at tertiary care pain clinics. Opioid therapy may not be beneficial for the long term. Perspective: Evidence-based treatment of chronic neuropathic pain provides long-term benefit in only about one-quarter of patients seen in tertiary care centers. Opioid therapy may not be beneficial., (Copyright © 2015 American Pain Society. Published by Elsevier Inc. All rights reserved.)

Background: Neuropathic pain (NeP), redefined as pain caused by a lesion or a disease of the somatosensory system, is a disabling condition that affects approximately two million Canadians., Objective: To review the randomized controlled trials (RCTs) and systematic reviews related to the pharmacological management of NeP to develop a revised evidence-based consensus statement on its management., Methods: RCTs, systematic reviews and existing guidelines on the pharmacological management of NeP were evaluated at a consensus meeting in May 2012 and updated until September 2013. Medications were recommended in the consensus statement if their analgesic efficacy was supported by at least one methodologically sound RCT (class I or class II) showing significant benefit relative to placebo or another relevant control group. Recommendations for treatment were based on the degree of evidence of analgesic efficacy, safety and ease of use., Results: Analgesic agents recommended for first-line treatments are gabapentinoids (gabapentin and pregabalin), tricyclic antidepressants and serotonin noradrenaline reuptake inhibitors. Tramadol and controlled-release opioid analgesics are recommended as second-line treatments for moderate to severe pain. Cannabinoids are now recommended as third-line treatments. Recommended fourth-line treatments include methadone, anticonvulsants with lesser evidence of efficacy (eg, lamotrigine, lacosamide), tapentadol and botulinum toxin. There is support for some analgesic combinations in selected NeP conditions., Conclusions: These guidelines provide an updated, stepwise approach to the pharmacological management of NeP. Treatment should be individualized for each patient based on efficacy, side-effect profile and drug accessibility, including cost. Additional studies are required to examine head-to-head comparisons among analgesics, combinations of analgesics, long-term outcomes and treatment of pediatric, geriatric and central NeP.

Background: Pain is one of the most common reasons for individuals to seek medical advice, yet it remains poorly managed. One of the main reasons that poor pain management persists is the lack of adequate knowledge and skills of practicing clinicians, which stems from a perceived lack of pain education during the training of undergraduate medical students., Objective: To identify gaps in knowledge with respect to pain management as perceived by students, patients and educators., Methods: A qualitative descriptive study was conducted. Data were generated through six focus groups with second- and fourth-year medical students, four focus groups with patients and individual semistructured interviews with nine educators. All interviews were audiotaped and an inductive thematic analysis was performed., Results: A total of 70 individuals participated in the present study. Five main themes were identified: assessment of physical and psychosocial aspects of pain; clinical management of pain with pharmacology and alternative therapies; communication and the development of a good therapeutic relationship; ethical considerations surrounding pain; and institutional context of medical education about pain., Conclusion: Participating patients, students and pain experts recognized a need for additional medical education about pain assessment and management. Educational approaches need to teach students to gather appropriate information about pain, to acquire knowledge of a broad spectrum of therapeutic options, to develop a mutual, trusting relationship with patients and to become aware of their own biases and prejudice toward patients with pain. The results of the present study should be used to develop and enhance existing pain curricula content.

There has been a surge in interest in medicinal cannabis in Canada. We conducted a questionnaire survey to determine the current prevalence of medicinal cannabis use among patients with chronic non-cancer pain, to estimate the dose size and frequency of cannabis use, and to describe the main symptoms for which relief was being sought. Over a 6-week period in mid-2001, 209 chronic non-cancer pain patients were recruited in an anonymous cross-sectional survey. Seventy-two (35%) subjects reported ever having used cannabis. Thirty-two (15%) subjects reported having used cannabis for pain relief (pain users), and 20 (10%) subjects were currently using cannabis for pain relief. Thirty-eight subjects denied using cannabis for pain relief (recreational users). Compared to never users, pain users were significantly younger (P=0.001) and were more likely to be tobacco users (P=0.0001). The largest group of patients using cannabis had pain caused by trauma and/or surgery (51%), and the site of pain was predominantly neck/upper body and myofascial (68% and 65%, respectively). The median duration of pain was similar in both pain users and recreational users (8 vs. 7 years; P=0.7). There was a wide range of amounts and frequency of cannabis use. Of the 32 subjects who used cannabis for pain, 17 (53%) used four puffs or less at each dosing interval, eight (25%) smoked a whole cannabis cigarette (joint) and four (12%) smoked more than one joint. Seven (22%) of these subjects used cannabis more than once daily, five (16%) used it daily, eight (25%) used it weekly and nine (28%) used it rarely. Pain, sleep and mood were most frequently reported as improving with cannabis use, and 'high' and dry mouth were the most commonly reported side effects. We conclude that cannabis use is prevalent among the chronic non-cancer pain population, for a wide range of symptoms, with considerable variability in the amounts used. Discussions between patients and health care providers concerning cannabis use may facilitate education and follow up, and would allow side effects and potential interactions with other medications to be monitored. Clinical trials of cannabis for chronic non-cancer pain are warranted.