Medical cannabis treatment was associated with sustained reductions in pain and improvements in sleep and quality of life among patients with inflammatory arthritis followed for up to two years, according to a new study.
Published September 9 in Clinical Medicine Insights: Arthritis and Musculoskeletal Disorders, the study analyzed 192 patients enrolled in the UK Medical Cannabis Registry who were prescribed cannabis-based medicinal products for pain associated with inflammatory arthritis. Researchers from Imperial College London and several other institutions conducted the analysis.
Patients were evaluated before beginning treatment and again after one, three, six, 12, 18 and 24 months. Researchers used multiple validated measures of pain, including the Brief Pain Inventory, Pain Visual Analogue Scale and Short-Form McGill Pain Questionnaire-2, along with measures of sleep, anxiety and overall health-related quality of life.
Medical cannabis treatment was associated with significant improvements in pain severity and pain interference at every follow-up point. Scores on the Pain Visual Analogue Scale and Short-Form McGill Pain Questionnaire-2 also improved at each assessment.
Sleep quality and overall health-related quality of life improved throughout the full 24-month follow-up period. Anxiety scores also improved during the first three months of treatment.
“The CBMP therapy was associated with reductions in pain and improvements in health-related quality of life,” researchers concluded.
Among the 192 patients, 27, or 14.1%, reported a total of 296 adverse events. About 43% were classified as mild and 45% as moderate, while approximately 13% were considered severe. Researchers reported no life-threatening adverse events.
The study was conducted by researchers affiliated with the Medical Cannabis Research Group at Imperial College London, Curaleaf Clinic, St George’s University Hospitals NHS Foundation Trust, King’s College London and the South London and Maudsley NHS Foundation Trust. Several of the researchers disclosed professional positions with Curaleaf Clinic.
Researchers cautioned that the observational design means the findings cannot establish that medical cannabis caused the improvements. There was no randomized placebo control group, and patients knew they were receiving cannabis-based medicines.
Still, the authors said the findings support conducting randomized controlled trials to determine the effectiveness of cannabis-based medicinal products for inflammatory arthritis-related pain.
