Presenting the outputs of the IASP Presidential Task Force on Cannabis and Cannabinoid Analgesia

Medical cannabis for refractory cancer-related pain in a specialised clinical service: a cross-sectional study

BACKGROUND AND OBJECTIVES

Cancer-related pain management in advanced stages presents a significant challenge that often requires a multidisciplinary approach. Although advancements in pharmacological and interventional therapies, a considerable number of patients still suffer from refractory pain, leading to unmet clinical needs. This study shares our experience with medical cannabis (MC) as a potential therapy for this specific population of patients with cancer-related refractory pain.

METHODS

In a cross-sectional study, 252 consecutive refractory cancer-related pain patients (mean age=61.71, SD=14.02, 47.6% males) filled out detailed self-report questionnaires. Of these, 126 patients (55%) were treated with MC and 105 patients (45%) were not.

RESULTS

Most patients received pain management from their oncologist, not a pain specialist. MC was mainly started for pain relief, sleep difficulties and anorexia. About 70% of patients reported subjective improvement from MC, with almost 40% reporting a significant improvement in coping with their illness. Side effects were generally mild, with fatigue and dizziness being the most common (21.78% and 23.46%, respectively). No patient required dedicated medical care for side effects. Of non-users, 65% had tried MC before and stopped due to lack of effectiveness or side effects (39.7% and 34.6%, respectively).

CONCLUSION

Refractory cancer pain necessitates innovative approaches. This registry highlights that MC can effectively improve symptoms in non-responsive patients, with favourable safety profiles for this vulnerable population.

Narrative bias ("spin") is common in randomised trials and systematic reviews of cannabinoids for pain

ABSTRACT

We define narrative bias as a tendency to interpret information as part of a larger story or pattern, regardless of whether the facts support the full narrative. Narrative bias in title and abstract means that results reported in the title and abstract of an article are done so in a way that could distort their interpretation and mislead readers who had not read the whole article. Narrative bias is often referred to as "spin." It is prevalent in abstracts of scientific papers and is impactful because abstracts are often the only part of an article read. We found no extant narrative bias instrument suitable for exploring both efficacy and safety statements in randomized trials and systematic reviews of pain. We constructed a 6-point instrument with clear instructions and tested it on randomised trials and systematic reviews of cannabinoids and cannabis-based medicines for pain, with updated searches to April 2021. The instrument detected moderate or severe narrative bias in the title and abstract of 24% (8 of 34) of randomised controlled trials and 17% (11 of 64) of systematic reviews; narrative bias for efficacy and safety occurred equally. There was no significant or meaningful association between narrative bias and study characteristics in correlation or cluster analyses. Bias was always in favour of the experimental cannabinoid or cannabis-based medicine. Put simply, reading title and abstract only could give an incorrect impression of efficacy or safety in about 1 in 5 papers reporting on these products.

Bridging the translational gap: adenosine as a modulator of neuropathic pain in preclinical models and humans

OBJECTIVES

This review aims to analyse the published data on preclinical and human experimental and clinical adenosine modulation for pain management. We summarise the translatability of the adenosine pathway for further drug development and aim to reveal subgroups of pain patients that could benefit from targeting the pathway.

CONTENT

Chronic pain patients suffer from inadequate treatment options and drug development is generally impaired by the low translatability of preclinical pain models. Therefore, validating the predictability of drug targets is of high importance. Modulation of the endogenous neurotransmitter adenosine gained significant traction in the early 2000s but the drug development efforts were later abandoned. With the emergence of new drug modalities, there is a renewed interest in adenosine modulation in pain management. In both preclinical, human experimental and clinical research, enhancing adenosine signalling through the adenosine receptors, has shown therapeutic promise. A special focus has been on the A1 and A3 receptors both of which have shown great promise and predictive validity in neuropathic pain conditions.

SUMMARY

Adenosine modulation shows predictive validity across preclinical, human experimental and clinical investigations. The most compelling evidence is in the field of neuropathic pain, where adenosine has been found to alleviate hyperexcitability and has the potential to be disease-modifying.

OUTLOOK

Adenosine modulation show therapeutic potential in neuropathic pain if selective and safe drugs can be developed. New drug modalities such as RNA therapeutics and cell therapies may provide new options.

Prevalence of cannabis use for pain management in Quebec: A post-legalization estimate among generations living with chronic pain

Background

Medical cannabis has been legal in Canada since 2001, and recreational cannabis was legalized in October 2018, which has led to a widespread increase in the accessibility of cannabis products.

Aims

This study aimed to estimate the prevalence of cannabis use among adults living with chronic pain (CP) and investigate the relationship between age and cannabis use for CP management.

Methods

A cross-sectional analysis of the COPE Cohort data set, a large Quebec sample of 1935 adults living with CP, was conducted. Participants completed a web-based questionnaire in 2019 that contained three yes/no questions about past-year use of cannabis (i.e., for pain management, management of other health-related conditions, recreational purposes).

Results

Among the 1344 participants who completed the cannabis use section of the questionnaire, the overall prevalence of cannabis use for pain management was 30.1% (95% confidence interval 27.7-32.7). Differences were found between age groups, with the highest prevalence among participants aged ≤26 years (36.5%) and lowest for those aged ≥74 years (8.8%). A multivariable logistic model revealed that age, region of residence, generalized pain, use of medications or nonpharmacological approaches for pain management, alcohol/drug consumption, and smoking were associated with the likelihood of using cannabis for pain management.

Conclusions

Cannabis is a common treatment for the management of CP, especially in younger generations. The high prevalence of use emphasizes the importance of better knowledge translation for people living with CP, rapidly generating evidence regarding the safety and efficacy of cannabis, and clinicians' involvement in supporting people who use cannabis for pain management.