What is Multiple Sclerosis?
Multiple sclerosis (MS) is a neurodegenerative disease of the central nervous system that is mediated by the immune system. Aside from trauma, multiple sclerosis is the leading cause of disability young adults . The average age of is around 30 years old, although presentation can occur from teenage years into forties or older . Although much remains to be discovered about the etiology of the disease, there are multiple known risk factors, including:
- Genetics: multiple genetic mutations that impact the immune system that have been shown to influence the risk of developing the disease . One of the largest risk factors is having a first-degree relative impacted by the disease .
- Gender: women have been shown to have an increased risk of developing multiple sclerosis compared to men .
- Geographic location: latitude (how close your location is in relation to the North or South Pole), has been shown to influence the risk of disease development. Regions closer to the equator have lower rates of disease that regions further away. One study showed that women in the Northern part of the US demonstrated higher rates of disease that women farther south [6-7].
- Sunlight and vitamin D levels: exposure to sunlight was shown to be protective for the development for MS  and vitamin D has been demonstrated to potentially be protective .
Multiple sclerosis can be difficult to diagnose, as many of the symptoms are not specific. It is important to consider in the differential diagnosis for appropriate patients, or else it may be missed. Common symptoms include:
- Muscle tremors and spasms
- Sleep disturbance
- Gait impairment
- Bowel/bladder dysfunction
- Cognitive impairment
For some patients, symptoms of multiple sclerosis will develop and remain stable, while others will experience a progressive decline in function and potentially death. There are currently many available therapies to prevent decline and maintain function, and it is important for patients and physicians to work closely to find the optimal regimen. These therapies have shown positive impact in some patients, while minimally impact disease in others, but most if not all therapies are designed to impact the course of the disease, not the symptoms the patient already has. Additional drugs are needed for previously mentioned symptoms and the medication burden can become quite severe. Although cannabis and cannabis-based products do not currently have any data to support their impact on disease progression (positively or negatively), there is data to suggest that they can provide symptomatic benefit to patients and improve quality of life.
Multiple Sclerosis and Cannabis
Medical cannabis is now available for prescription in many states to assist in symptom management for patients with multiple sclerosis. Spasticity is the disordered regulation of nerves controlling sensory and motor function, resulting in intermittent or sustained contractions of muscles. It is one of the most common symptoms of multiple sclerosis and can severely limit mobility and function. Currently available therapies to manage spasticity include baclofen, tizanidine, and dantrolene, however each of these medicals has potentially serious side effects (ex: weakness, liver toxicity). And the evidence for non-pharmacologic treatment such as physical therapy and electric stimulation of muscles, has not proven beneficial .
Fortunately, cannabis-based therapies have demonstrated promise for symptom management in patients with multiple sclerosis. One found that nabiximols and nabilone resulted in potential improvements in spasticity, with no difference in type of cannabinoid used . Another study examining patient-reported improvement of disease impression was 44% more likely in patients on a cannabis-based therapy .
Two of the largest individual studies, the CAMS and MUSEC trials, also demonstrated the potential for cannabis to decrease muscle spasticity. In the CAMS trial, patients experienced subjective relief of symptoms and objective improvement in spasticity through standardized measured outcomes . Results from the MUSEC trial supported this outcome, as the proportion of patients who experienced relief from muscle stiffness was almost 2x greater in the cannabis group than the placebo (29.7% vs 15.7%). Subjects in this trials also experienced significant relief from body pain, muscle spasms, and improved sleep quality.
The most popular current therapies available to treat symptoms of multiple sclerosis often come with potentially significant side effects. To date, cannabis and cannabis-based products have demonstrated promise in providing relief of such symptoms with a potentially better side effect profile. It is important to discuss the potential benefits of cannabis products on your symptoms with your doctor or a trained professional in order to determine if cannabis therapy is appropriate for you.
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