Comparing the effects of medical cannabis for chronic pain patients with and without co-morbid anxiety: A cohort study

ABSTRACT

Introduction

There is growing evidence on the efficacy of cannabis-based medicinal products (CBMPs) for chronic pain (CP). Due to the interaction between CP and anxiety, and the potential impact of CBMPs on both anxiety and CP, this article aimed to compare the outcomes of CP patients with and without co-morbid anxiety following CBMP treatment.

Methods

Participants were prospectively enrolled and categorized by baseline General Anxiety Disorder-7(GAD-7) scores, into ‘no anxiety’(GAD-7 < 5) and ‘anxiety’(GAD-7 ≥ 5) cohorts. Primary outcomes were changes in Brief Pain Inventory Short-Form, Short-form McGill Pain Questionnaire-2, Pain Visual Analogue Scale, Sleep Quality Scale (SQS), GAD-7 and EQ-5D-5L index values at 1, 3 and 6 months.

Results

1254 patients (anxiety = 711; no anxiety = 543) met inclusion criteria. Significant improvements in all primary outcomes were observed at all timepoints (p < 0.050), except GAD-7 in the no anxiety group(p > 0.050). The anxiety cohort reported greater improvements in EQ-5D-5L index values, SQS and GAD-7(p < 0.050), but there were no consistent differences in pain outcomes.

Conclusion

A potential association between CBMPs and improvements in pain and health-related quality of life (HRQoL) in CP patients was identified. Those with co-morbid anxiety reported greater improvements in HRQoL.

KEYWORDS:

• Cannabis
• cannabidiol
• tetrahydrocannabinol
• pain
• chronic pain
• anxiety

Acknowledgments

The authors confirm that the PI for this paper is Mikael H Sodergren and that he had direct clinical responsibility for patients. This work has previously been presented at the International Cannabinoid Research Society Conference 2022.

Declaration of Interest

S Erridge undertakes paid consultancy work at Sapphire Medical Clinics. C Holvey is chief clinical pharmacist at Sapphire Medical Clinics. R Coomber is a director at Sapphire Medical Clinics. The views expressed are those of the author(s) and not necessarily those of the NHS. Ross Coomber has no shareholdings in pharmaceutical companies, while A Usmani and M Sajad are pain specialists at Sapphire Medical Clinics (London). J Hoare is a consultant in gastroenterology at Sapphire Medical Clinics (London) while SA Khan is a consultant in palliative medicine at Sapphire Medical Clinics (London. MW Weatherall is also a consultant Sapphire Medical Clinics (London). JJ Rucker is a consultant psychiatrist, a director and a shareholder at Sapphire Medical Clinics (London). He is is funded by a fellowship (CS-2017-17-007) from the National Institute for Health Research (NIHR). He also leads the Psychedelic Trials Group at King’s College London. King’s College London receives grant funding from COMPASS Pathways PLC to undertake phase 1 and phase 2 trials with psilocybin. COMPASS Pathways PLC has paid for J Rucker to attend trial related meetings and conferences to present the results of research using psilocybin. He also has undertaken paid consultancy work for Beckley PsyTech and Clerkenwell Health. Payments for consultancy work are received and managed by King’s College London and he does not benefit personally. James Rucker has no shareholdings in pharmaceutical companies. M Platt is a consultant in pain services at Sapphire Medical Clinics (London). MH Sodergren is a consultant hepatopancreatobiliary surgeon at Imperial College NHS Trust, London. He is also the Managing Director of Sapphire Medical Clinics (London) and the Chief Medical Officer of Curaleaf International. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Reviewer Disclosures

Peer reviewers on this manuscript have no relevant financial or other relationships to disclose.

Author Contributions

Study conception and design: L. Bapir, S. Erridge, C. Holvey, R. Coomber, J.J. Rucker, M.H. Sodergren.

Acquisition of data: L. Bapir, S. Erridge, M. Nicholas, M. Pillai, N. Dalavaye, C. Holvey, R. Coomber, J. Hoare, S. Khan, M.W. Weatherall, J.J. Rucker, M. Platt.

Analysis and interpretation of data: L. Bapir, S.Erridge, M.H.Sodergren.

Drafting of manuscript: L. Bapir, S.Erridge, MH.Sodergren.

Critical revision: L. Bapir, S. Erridge, M. Nicholas, M. Pillai, N. Dalavaye, C. Holvey, R. Coomber, J. Hoare, S. Khan, M.W. Weatherall, J.J. Rucker, M. Platt, M.H. Sodergren.

All authors have contributed to and approved the final manuscript. All conditions as previously stated by the ICMJE have been met.

Data Availability Statement

Data that support the findings of this study are available from the UK Medical Cannabis Registry (https://ukmedicalcannabisregistry.com/). Restrictions apply to the availability of these data. Data specifications and applications are available from the corresponding author.

Ethics Approval

In the UK, ethics approval is not required for purely registry-based studies.

Patient Consent Statement

All participants completed written, informed consent prior to enrolment in the registry.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/14737175.2023.2181696

Additional information

Funding

This study was not funded.