|Multiple Sclerosis: The invisible brain war and facts for the Drug Information Pharmacist|
1University of Ghana, School of Distance Education, Department of Pharmacology, Accra
2Interpharma Limited, Koforidua
Every organism’s immune system is designed to protect it against diseases by identifying and destroying pathogens and other foreign materials. In a pathological state however, the immune responses are directed against, and damage, the body’s own tissues (autoimmunity). Common examples of autoimmune disease include type 1 diabetes, rheumatoid arthritis, psoriasis and multiple sclerosis. In this review we shall highlight some on Multiple Sclerosis (MS) and the facts that come handy for a drug information pharmacist.
Multiple Sclerosis is a chronic neurodegenerative disorder that is unpredictable and poorly understood. Neurodegenerative disorders primarily affect the human brain and are characterized by a slow progressive loss of neurons in the central nervous system (CNS). The progressive loss of neural matter leads to deficit in specific brain functions such as memory, movement, cognition, and speech, among others depending on the area of damage. Alzheimer’s disease, Parkinson’s disease, amyotrophic lateral sclerosis, Huntington’s disease, multiple system atrophy, and MS are neurodegenerative diseases. The course of each disease usually extends over a decade with the onset of degeneration preceding clinical manifestations by over a decade. It is noteworthy that most of these neurodegenerative diseases are currently incurable and debilitating with neuronal cell death as their consequence.
MS reportedly affects 2.5 million people worldwide with about 200 people being diagnosed each week in the United States. It typically affects persons aged 20-40 years. Women are affected twice as often as men are due to occupational stress, cigarette smoking, obesity, birth control, and late childbirth. In Ghana, there is limited data on the prevalence, incidence, and mortality rate associated with MS. This is understandably so because MS is not an ailment of common occurrence in Ghana. An understanding of the intricate and unpredictable nature of MS is expedient to fueling the progress that changes the lives of MS patients and ultimately reduces the burden of the disease to the barest minimum.
Neuroinflammation in MS
Traditionally, the CNS was considered to be limited in inflammatory capacity due to the existence of the blood-brain barrier, which restricts the passage of cells and many inflammatory substances from the blood to the brain. Studies have however found that the CNS is actually immunologically specialized with an innate immune response via microglial activity. The microglia provide the first line of defense whenever injury or disease threatens in the CNS. Once activated, microglia produce a spectrum of inflammatory mediators, including eicosanoids, cytokines, chemokines, reactive free radicals, and proteases, which modulate immunologic actions but may also act on neurons to alter their function.
In MS, this inflammatory process is faulted and unregulated, such that the immune system attacks the protective myelin sheath that covers nerve fibers and destroys them. These protective myelin sheaths are important to protect neuronal axons, which aid in effective communication between nerves following an injury. However in MS, excessive inflammation causes lesions on the myelin sheath resulting in demyelination. Eventually, demyelination causes the axons to be exposed to injury and deteriorate or become permanently damaged. This damage to neuronal axons results in slowed conduction and eventually conduction block. Although myelin sheaths regenerate after an initial damage, the sustained uncontrolled inflammatory process drives disease progression.
The diagram below provides an illustration of nerves affected by MS.
Figure 1. Multiple sclerosis damages nerve cells
Etiology of MS
The exact cause of MS is currently unknown. It is however reported to be triggered by factors such as age, gender, family history, race, geography, certain infections, autoimmune diseases, and smoking. Generally, individuals who are mostly affected by MS are between the ages of 15 and 60 years, with women being twice more likely to develop MS than men are.
Scientific reports have also linked the development of MS to gene mutation. The genetic linkage suggests why individuals whose relatives have had MS are at a higher risk of developing the disease. With respect to race, dark-skinned persons are at a lower risk of developing MS; however, the course of the disease is known to be more aggressive in them. Similarly, individuals living in tropical zones are at a comparatively lower risk of developing MS than those living in temperate zones are. Additionally, differences in the level of vitamin D, which is produced by bodies when exposed to sunlight, have been revealed to be a contributing factor to MS development; this is because vitamin D helps to lower an individual’s risk of developing MS.
Furthermore, individuals with Epstein-Barr virus infections and autoimmune disorders such as thyroid disease, insulin-dependent diabetes mellitus, and inflammatory bowel disease are at a high risk of developing MS. Finally, smoking increases the severity of MS and hastens the progression of the disease.
Clinical manifestations of MS
About 2.3 million people across the globe are living with MS; however, no two patients present exactly the same symptoms, which makes MS very difficult to diagnose at first appearance. Patients suffer various degrees of intensity of the condition. Some may present with fatigue and impaired vision, others may lose their sense of balance and coordination, whereas others may develop a feeling of numbness in their arms and legs.
Muscle stiffness, bladder and bowel problems, difficulty walking, short-term memory loss, mood swings and, in severe cases, partial or complete paralysis have also been described as part of the manifestations. Because myelin sheaths are able to regenerate after a couple of days or weeks, MS symptoms can often disappear by themselves, only to return with a higher severity months later. Living with MS is highly unpredictable with a relapse-remitting course of the disease.
The diagnosis of MS requires a lot of expertise in neurological disorders since there are no specific tests to detect it. Instead, investigations such as blood tests (serological markers), magnetic resonance imaging, and lumbar puncture are performed to help rule out conditions such as vasculitis and spinal cord neoplasms that present with similar symptoms. Prompt treatment is critical in MS in order to prevent affected individuals from developing complications, which result in a poorer prognosis. Patients may develop untoward conditions such as depression, epilepsy, leg paralysis, muscle stiffness, impaired sexual function, impaired bowel movement, and urinary tract infections if the disease is not managed appropriately.
Management of MS by a drug information pharmacist
Currently there is no cure for MS. The main goal of treatment is therefore to maximize the quality of life of patients by managing presenting symptoms. Clinicians also aim at shortening exacerbations and slowing the progression of the disease. Physiotherapy and medications that suppress the immune system also help to manage the symptoms and slow disease progression. Rehabilitation can also help prevent complications and secondary disabilities from developing. The treatment options include:
a) Corticosteroids: These are administered to reduce neuronal inflammation and suppress immune hyperactivity. Examples include oral prednisolone and intravenous hydrocortisone.
b) Beta interferons: These are injected under the skin or into the muscle to reduce the frequency and severity of relapses.
c) Ocrelizumab: This humanized immunoglobulin antibody has been approved to treat both the relapse-remitting and primary progressive forms of MS.
d) Muscle relaxants: These are indicated for the management of painful muscle stiffness and spasms associated with MS. Examples include baclofen and tizanidine.
e) Disease modifying drugs
The use of medications in MS is very delicate and needs knowledgeable and skilled personnel led by a drug information pharmacist to ensure great pharmaceutical care to the patient. The knowledge base and capacity of a drug information pharmacist can help assess the potential for drug interactions before initiating treatment with a new medication. Moreover, since most MS patients present with comorbid conditions such as depression, it is expedient to identify the kind of medication to use so as not to exacerbate the presenting symptoms. Indeed a drug information pharmacist with specialty in neurological conditions can do a comprehensive medication review in order to harness information that will be good in obtaining positive therapeutic outcomes. Proper administration of some of these medications can be done effectively in conjunction with a drug information pharmacist. After the right doses of medications have been administered via the appropriate routes, the pharmacist can also monitor patients to ensure that they are deriving much benefit from the therapy.
In public health, a key element of establishing the true burden of disease lies in case detection. Unfortunately the unpredictable nature of MS and the lack of a strong diagnostic method pose several challenges to medical professionals, from nurses, to doctors, to pharmacists, in case detection. Maximized case detection within a community implies that all members of that community are aware of the presentation and diagnosis of the disease, with the highest awareness required among healthcare professionals at the primary healthcare level.
In conclusion, let us all embrace the challenge of educating the public on MS with passion, provide life-changing programs, and help guarantee a supportive community for those who need it.