Research study · Clinical Medicine Insights: Arthritis and Musculoskeletal Disorders · 2026
UK Medical Cannabis Registry: An Updated Analysis of Inflammatory Arthritis
Verified on PubMed Oxford CEBM Level 1B: Randomized Controlled Trial
A 2026 randomized controlled trial in Clinical Medicine Insights: Arthritis and Musculoskeletal Disorders tested medical cannabis in arthritis. The results were encouraging but cannot prove the treatment worked. This study shows that people with arthritis pain who used medicinal cannabis in this clinic setting tended to report less pain and better daily functioning over two.
In plain language
Study overview
This study followed 192 adults in the United Kingdom who had long-lasting pain from arthritis and were given medicinal cannabis by a private clinic. Each person filled in questionnaires about pain, mood, sleep and daily life over two years. The researchers looked at how these answers changed over time.
Findings
The results were encouraging but cannot prove the treatment worked. Patients reported less pain and better quality of life over the two years, and most side effects were mild or moderate, such as tiredness and dry mouth.
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The deeper readScientific analysis
Aim: Cannabis-based medicinal products (CBMPs) are an emerging therapeutic option for pain in inflammatory arthritis, yet clinical evidence remains limited. This study aimed to evaluate changes in pain-specific and general health-related outcomes in patients with inflammatory arthritis treated with CBMPs and to characterize the safety profile by examining the incidence and nature of adverse events. Methods: Patients treated with CBMPs for inflammatory arthritis-associated pain for at least 24 months were identified from the UK Medical Cannabis Registry. Primary outcomes included changes in patient-reported measures (BPI, Pain VAS, SF-MPQ-2, EQ-5D-5L, GAD-7, and single-item sleep quality scale) at 1, 3, 6, 12, 18, and 24 months vs baseline. Adverse events were recorded and analysed. Statistical significance was set at P < .050. Results: A total of 192 patients met inclusion criteria. CBMP initiation was associated with improvements in BPI Interference, BPI Severity, Pain VAS, SF-MPQ-2, sleep quality, and EQ-5D-5L index values at all follow-up time points (P < .010) and in GAD-7 scores up to 3 months (P < .001). Twenty-seven patients (14.06%) reported 296 adverse events: 126 (42.57%) mild, 132 (44.59%) moderate, and 38 (12.84%) severe. No life-threatening events occurred. Conclusion: CBMP therapy was associated with reductions in pain and improvements in health-related quality of life among individuals with inflammatory arthritis. Although causality cannot be inferred from this observational design, these findings support the need for randomized controlled trials.
The paper
Citation
Sajeev A, Erridge S, Datta A, Clarke E, McLachlan K, Coomber R, et al. UK Medical Cannabis Registry: An Updated Analysis of Inflammatory Arthritis. Clinical Medicine Insights: Arthritis and Musculoskeletal Disorders (2026). PubMed 42724108 · DOI
Limitations the authors noted
Observational design without placebo control or blinding; causation cannot be inferred. Potential regression to the mean, recall bias, and expectancy bias from subjective retrospective PROMs. Selection bias: single private clinic, patients able to afford treatment, 53.65% current cannabis users at baseline. High attrition handled by multiple imputation; reported attrition and missingness are substantial. Potential confounding by concurrent analgesics (35.94% on opioids at baseline) and illicit cannabis use. Heterogeneous CBMP formulations and doses; no formal sleep studies. Industry-affiliated authors (Curaleaf Clinic employees).
In practice
Why this matters
This study shows that people with arthritis pain who used medicinal cannabis in this clinic setting tended to report less pain and better daily functioning over two years, but it cannot tell us whether the cannabis itself caused those changes, since there was no comparison group that did not receive it. It is a useful reason to run properly controlled trials, which are still missing for this condition. It does not tell you what dose, product or form would suit any particular person, or how long benefits last beyond two years in other settings.
Frequently asked questions
Clinical Questions & Answers
What were the primary clinical findings regarding cannabinoids and Adverse events?
The results were encouraging but cannot prove the treatment worked. Patients reported less pain and better quality of life over the two years, and most side effects were mild or moderate, such as tiredness and dry mouth.
What study limitations or clinical safeguards should patients keep in mind?
Observational design without placebo control or blinding; causation cannot be inferred. Potential regression to the mean, recall bias, and expectancy bias from subjective retrospective PROMs. Selection bias: single private clinic, patients able to afford treatment, 53.
Browse related research
Condition: Adverse events Condition: Arthritis Condition: Pain Topic: Cannabis Topic: Medical cannabis
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Reviewed by Dr. Caplan on October 17, 2026.
This page is general education about a published study. It is not medical advice and does not create a doctor-patient relationship. For care specific to you, book a consultation.
