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Characteristics of People Seeking Prescribed Cannabinoids for the Treatment of Chronic Pain: Evidence From Project Twenty 21

a Doctors book called pain management


Anne Katrin Schlag, Michael Lynskey, Alan Fayaz, Alkyoni Athanasiou-Fragkouli, Brigitta Brandner, Barbara Haja, Elizabeth Iveson and David J. Nutt


June 14, 2022

Medical Cannabis for Chronic Pain

Chronic pain is a pervasive, and potentially disabling condition. In the UK it is estimated to affect between one third and one half of the adult population, contributing to major social and economic costs. However, despite considerable advances in our understanding of pain mechanisms over the past half a century, there remains a lack of effective pharmacological treatments for chronic pain symptoms.

Prescribed cannabinoids, also known as Cannabis-Based Medicinal Products (CBMPs) have been legal in the UK since 2018, and are increasingly being used to treat a variety of conditions, with one of the most frequent conditions being chronic pain. This paper describes the characteristics of individuals seeking prescribed cannabinoids for the treatment of chronic pain in Project Twenty 21, a UK based real world data registry of prescribed cannabis patients. 

By 1st November 2021 data were available for 1,782 people who had sought treatment with medical cannabis as part of Project Twenty 21. The most common diagnosis among this cohort was chronic pain with 949 (53.5%) of the cohort reporting a primary condition related to chronic pain. 

Of the 949 people reporting chronic pain as a primary condition, 54.7% were male and their average age was 42.0 years (range = 18–84). Patients reported a low quality of life and high levels of comorbidity: people reported an average of 4.6 comorbid conditions with the most common comorbid conditions including anxiety, depression, insomnia and stress, which are often also treated with CBMPs. This high number of co-morbid conditions experienced also highlights the benefits of observational databases and real world evidence (RWE) as many of these patients would have automatically been excluded from more formal randomised controlled trials (RCTs). 

A range of cannabinoid products were prescribed with the most common products being classified as high THC flower (48.5%). The majority of patients also reported using at least one other prescribed medication (68.7%). 

There was considerable variation in the types of chronic pain, comorbid pathology and in the characteristics of products being prescribed to treat these conditions. Together, this evidence supports the utility of real world evidence, as opposed to clinical trial approaches to studying the potential benefits of prescribed cannabinoids in treating chronic pain. 

Our results confirm the complexity underlying the patient experience and the impact of chronic pain. The management of chronic pain remains a major medical challenge, and it is important to include the clinical experience of patients and clinicians to inform treatment pathways and specific treatments. Our findings reflect results from other national and international databases, building up to a pattern of evidence, but the value of CBMPs for pain management remains controversial. The long-term impact of CBMPs, for chronic pain as well as for other conditions, still needs to be fully understood. In the UK, the relative lack of expert-based recommendations, clinical experience, education and patient support for these medicines still presents a challenge for patients and clinicians. 

Longitudinal RWE studies, such as those reported here, can contribute to the scientific evidence base on CBMPs, which should be acknowledged by healthcare professionals and policy-makers, when formulating decisions about prescribing medical cannabis. 

Acknowledgements: We thank our partners whose generosity is enabling Project Twenty21 patients to receive their CBMPs at a reduced rate: Alta Flora, Cellen Biotech Ltd, JMCC Group, Khiron Life Sciences Corpand Lyphe Group.

For open access to the full report of this research, see below:

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