Multiple sclerosis (MS) is a chronic disease of the central nervous system (CNS). Typically, in MS, nervous system components become inflamed, resulting in damage called lesions and some tissue loss may occur^1,2. MS is a major cause of neurological disability among young adults^1,2. Patients can have a variable range of symptoms in MS. These can include changes in movement, balance or vision¹. “Hidden” symptoms, such as fatigue, pain, or mental health conditions may also occur¹. This is unsurprising, given the complexity of the nervous system and the range of CNS areas that may be affected by MS¹.

MS is categorized based on initial disease course as¹:

• Relapsing–remitting MS (RRMS)
  • Most common type of MS, seen in 85–90% of patients suffering from MS
  • Distinguishing feature is relapse – the appearance of new symptoms or worsening of pre-existing symptoms
• Primary progressive MS (PPMS)
  • Affects 10–15% of MS patients

Additionally, over the course of time, secondary progressive MS (SPMS) may occur¹:

• Most RRMS cases may develop into this progressive type
• Key feature is progressive accumulation of disability with or without relapses

MS is a global problem. Worldwide, approximately 2.8 million people currently live with MS¹. In Belgium, the Charcot Foundation estimated, in 2018, that approximately 13,500 people were affected by MS³.

People living in regions more distant from the equator exhibit a higher risk of developing MS than those close to the equator¹. The incidence rate (number of new cases diagnosed each year) has been reported to be higher in Northern Europe compared with Southern and Eastern Europe¹.

These regional variations can be due to differences in genetic, environmental and healthcare factors across territories and countries¹.

Women are diagnosed with RRMS nearly 3 times more than men. In contrast, men and women are similarly affected by PPMS².

Most patients are diagnosed between the ages of 20 and 40 years¹. Recently, diagnosis of MS in people over 50 years old has been increasing. Combined with improvements in MS lifespan and prognosis, this means that MS is currently more prevalent in older populations¹.

Image

Demyelination - The neuron on the left shows a healthy myelinated axon, while the neuron on the right shows an axon with damaged or missing myelin sheaths