Understanding Multiple Sclerosis
Multiple Sclerosis (MS) is an autoimmune, neurodegenerative disease that affects the central nervous system (CNS). The disease is characterised by the immune system mistakenly attacking the protective layer around nerve fibres (demyelination), leading to nerve damage and scarring (gliosis).
In 2020, it was estimated that approximately 2.8 million people worldwide had MS, with women being twice as likely to be affected.
There are four main types of MS (relapsing-remitting, primary progressive, secondary progressive and progressive-relapsing), each characterised by different disease onset and patterns.
As many diverse regions of the CNS may be affected, MS can cause a broad range of symptoms that vary greatly from person to person.Patients may experience motor and sensory symptoms, as well as psychiatric symptoms. Chronic pain is also very common, affecting between 50% and 75% of MS patients.
Management often involves disease-modifying therapies to slow progression, alongside treatments to manage ongoing symptoms. However, the efficacy and tolerability of currently recommended therapies for symptomatic relief, especially pain, are often limited, highlighting a critical need for alternatives.
Medical Cannabis and Multiple Sclerosis
In the UK, nabiximols, which contains tetrahydrocannabinol (THC) and cannabidiol (CBD) from the cannabis plant, is licensed for MS-induced spasticity. Other forms of medical cannabis may be prescribed for individuals with MS, though further evaluation is needed to understand the outcomes of these patients
A recent analysis published in Medical Cannabis and Cannabinoids evaluated real-world data collected through the UK Medical Cannabis Registry to investigate changes in MS-specific and general health-related patient-reported outcome measures and adverse events in individuals prescribed medical cannabis for multiple sclerosis.
What is the UK Medical Cannabis Registry?
The UK Medical Cannabis Registry is a patient registry established by Curaleaf Clinic in 2019. It gathers information on patients in the UK who are prescribed medical cannabis.
- It helps collect real-world data on different conditions and the use of medical cannabis.
- It tracks patient-reported changes in symptoms and overall quality of life, as well as any reported adverse events (side effects).
- A previous analysis of the UK Medical Cannabis Registry has assessed the outcomes in patients with MS over 6 months of therapy.
- The recent updated analysis on MS looked at the information from 203 patients over 24 months.
Key Findings of the Analysis
The study looked at whether patients noticed changes in their symptoms and general wellbeing after starting their medical cannabis prescriptions. The main way they did this was through patient-Reported Outcome Measures (PROMs), which are surveys completed by the patients themselves.
The findings showed some trends in how patients reported their health over the two-year period:
MS-Specific Outcomes: Changes were seen at all follow-up times across various subscales of the MSQOL-54, including:
- Pain
- Energy
- Physical function and physical role limitations
- Health distress
- Mental health and physical health composite scores.
These findings suggest that, for this group of patients, the use of medical cannabis was generally associated with sustained changes in several key aspects of self-reported health-related quality of life over two years.
Changes in Sleep and Anxiety
Beyond MS-specific symptoms, the registry also monitored general health concerns common in MS patients, specifically sleep and anxiety.
Sleep Quality
- Patients reported changes in sleep quality (measured by the Single-Item Sleep Quality Scale or SQS) at all follow-up times compared to the start of the study, up to 24 months.
- Almost half of the patients (47.29%) achieved a minimal clinically important difference (MCID) in their SQS scores by 24 months, meaning the change they experienced was significant enough to feel like a real difference in their life.
Anxiety
- Self-reported anxiety scores (measured by the Generalised Anxiety Disorder-7 or GAD-7) showed changes at 1, 3, 6, and 18 months.
- About one-third of patients (37.44%) achieved an MCID in their GAD-7 scores by 24 months.
Adverse Events
It is essential to understand that any medicine can have side effects. In this study, the adverse events were reported as follows:
- Prevalence: A total of 278 adverse events were reported by 26 (12.81%) patients.
- Severity: Most of the reported events were described as mild (32.73%) or moderate (49.64%) in severity.
The most commonly reported adverse events were:
- Fatigue (13.30%)
- Spasticity (8.37%)
- Generalised Muscle Weakness (7.88%)
- Somnolence (drowsiness) (7.88%)
Note: Fatigue and spasticity are common symptoms of MS itself. Since this was an observational study and not a controlled trial, the researchers noted, as with all outcomes, it is unclear whether these events occurred because of the medical cannabis treatment or were a reflection of another factor.
Factors Associated with Adverse Events
The analysis also identified some factors associated with a higher likelihood of reporting a side effect:
- Age: Being in the 41-60 age range.
- CBD Dose: Being on a higher daily CBD dose (≥ 31 mg/day).
Prior experience using cannabis (either as a current user or ex-user) before starting the treatment was associated with a lower likelihood of reporting an adverse event.
Key Considerations for Patients and Next Steps
The findings from this large, long-term registry study give us a better picture of how medical cannabis is being used by patients with MS in the UK.
Limitations of Observational Data
It is crucial to remember that this was an observational study. This means it simply watched what happened to patients already prescribed medical cannabis. As it didn’t use a control group or placebo, the study cannot establish a definitive causal link between medical cannabis and the reported outcomes.
The authors of the study suggest that more rigorous, long-term randomised controlled trials are needed to properly assess medical cannabis treatment for MS.
Individualised Care is Key
- Dosage and Formulation: Most patients in this study used a combination of dried flower (flos) and oil. The proportion of patients using only sublingual oils decreased over time. The researchers note that different routes of administration have different effects (e.g., inhaled preparations are faster-acting, while sublingual preparations have a longer duration).
- Personalised Treatment: The complex nature of MS means that how the disease progresses and how a patient responds to treatment can vary widely. The authors recommend a personalised approach to symptom management.
If you are living with MS and are considering medical cannabis, the first step is always to discuss your condition and treatment options with a specialist doctor.
Disclaimer: This blog post is for informational purposes only and does not constitute medical advice. It provides factual information on research findings. It does not make claims of efficacy or safety of medical cannabis. Patients should always consult a qualified healthcare professional before making any decisions about their treatment.