Louis Roller takes a look at multiple sclerosis
Multiple sclerosis (MS) is a demyelinating disease in which the insulating covers of nerve cells in the brain and spinal cord are damaged.
The cause of multiple sclerosis is unknown. It’s considered an autoimmune disease in which the body’s immune system attacks its own tissues.
In the case of MS, this immune system malfunction destroys myelin (the fatty substance that coats and protects nerve fibres in the brain and spinal cord).This damage disrupts the ability of parts of the nervous system to communicate, resulting in a range of signs and symptoms, including physical, mental, and sometimes psychiatric problems.
Approximately 23,000 Australians have MS, and it is estimated that every year the number of people diagnosed increases by 4%. Worldwide, MS affects about 2.5 million people.
The ratio of women with MS to men with the disease is two to one.
Because of the difficulty in diagnosing the disease, and because symptoms can be completely invisible, these numbers can only be an estimation.
The cause of the disease is not known, but theories include that it is an autoimmune disease, it is caused by genetic or environmental factors, or that it is caused by a virus.
There is currently no known cure for MS. It is an unpredictable disease that affects different people in different ways.
MS is diagnosed by a range of tests including MRI to detect lesions in the central nervous system, a physical examination to check reflexes and responses, blood tests, lumbar punctures and a range of other tests to measure nerve activity.
Sometimes it can take years to reach a diagnosis because there is no one test for MS. A diagnosis of MS will be made if there is evidence of lesions in different parts of the central nervous system, at different times, with no alternative explanation other than MS.
Types of MS
- Relapsing-remitting MS (RRMS) is characterised by clearly defined relapses of increased disease activity and worsening symptoms. These are followed by remissions in which the disease doesn’t progress. Symptoms may improve or disappear during remission. Approximately 85% of patients are diagnosed with RRMS at onset.
- Untreated, about 50% of people with RRMS transition to secondary-progressive MS (SPMS) within a decade of the initial diagnosis; health steadily declines.
- Primary-progressive MS (PPMS) is diagnosed in about 10% of MS patients at onset. People with PPMS experience a steady progression of the disease with no clear relapses or remissions. The rate of PPMS is equally divided between men and women. Symptoms usually begin between the ages of 35 and 39.
- Progressive-relapsing MS (PRMS) is the rarest form of MS, representing about 5% of MS patients. People with PRMS have clear relapses combined with a steady progression of the disease.
Approximately 10 to 20% of people with MS have a benign course (benign MS) of the disease. This means they have only mild symptoms and little disease progression. However, long-term studies show that some of these people experience some progression after 10 to 20 years. About 1% of patients develop an aggressive form of MS that progresses very rapidly.
Symptoms are varied and unpredictable, depending on which part of the central nervous system is affected and to what degree. No two cases of MS are the same and symptoms, depending on where MS lesions develop on the brain and spinal cord, can manifest in many different ways.
The symptoms can be any combination of the five major health problems, including:
- Motor control—muscular spasms and problems with weakness, coordination, balance and functioning of the arms and legs.
- Fatigue—including heat sensitivity.
- Other neurological symptoms—including vertigo, pins and needles, neuralgia and visual disturbances.
- Continence problems—including bladder incontinence and constipation.
- Neuropsychological symptoms—including memory loss, depression and cognitive difficulties.
Long-term treatment with immunomodulators may be used in patients with relapsing forms of MS with the aim of reducing the frequency of relapses and slowing the progression of disability.
Interferons beta-1a, beta-1b and glatiramer are used for relapsing-remitting MS; they seem to slow the disease.
Interferon beta-1b is also marketed for secondary progressive MS with relapses.
Natalizumab is given by IV infusion for relapsing-remitting MS.
Fingolimod and teriflunomide are oral drugs for relapsing MS. Compared to IM interferon beta-1a, fingolimod modestly reduced relapse rate but there was no difference in disability progression over 12 months.
Dimethyl fumarate an oral drug for relapsing-remitting MS.
The role of the pharmacist is to:
- be up to date with the latest medicines available for the treatment of MS;
- be able to explain to MS sufferers the likely course of their disease;
- refer patients when MS might be a possibility;
- counsel appropriately on the MS medications and life-style changes; and
- advise patients about MS organisations and the plethora of websites available; a good starting point is:https://www.msaustralia.org.au/what-ms.
Associate Professor Louis Roller, from the Faculty of Pharmacy and Pharmaceutical Sciences Monash University, was the 2014 recipient of the PSA Lifetime Achievement Award.