If you’ve recently been diagnosed with MS, experiencing symptoms, or supporting someone with MS, learning about MS is an important part of managing life with it. More than 33,000 Australians live with MS, and Australia has one of the highest rates in the world ^[1]. Understanding the basics can help you feel more in control and work better with your healthcare team.

What You Need to Know

What Multiple Sclerosis Is

MS is a long-term condition where your immune system, which normally fights off infections, mistakenly attacks your own nervous system. Specifically, it targets myelin, the protective coating around nerve fibres in your brain and spinal cord ^[3].

Think of myelin like insulation around electrical wires. When it’s damaged, signals between your brain and body can slow down, get mixed up, or stop completely. This is what causes MS symptoms.

The word “sclerosis” means scarring. When your immune system attacks the myelin, it leaves patches of scar tissue (called lesions) in your brain and spinal cord ^[3]. These scars can be tiny or quite large.

Why Understanding MS Matters

MS is the most common cause of neurological disability in young adults. Worldwide, approximately 2.9 million people were living with MS as of 2023, up from 2.3 million in 2013 ^[2]. Australia has particularly high rates, especially in southern regions like Tasmania ^[1].

Early diagnosis and treatment make a real difference. Research shows that starting effective medication early helps people maintain better function throughout their lives ^[4].

How MS Affects Your Nervous System

Your central nervous system, your brain, spinal cord, and optic nerve, is your body’s control centre. It sends and receives messages through nerve fibres that control everything from movement to vision, balance, and thinking.

In MS, several things happen:

The myelin attack: Your immune system mistakes myelin for a threat and sends inflammatory cells to attack it. This is called demyelination ^[3].

The communication breakdown: Once myelin is damaged, nerve signals can’t travel properly. Imagine trying to make a phone call with a damaged cable – the message might not get through or might come through garbled.

The scar tissue: After each attack, your body tries to repair the damage but leaves behind scar tissue. These are what doctors see on MRI scans ^[5].

Location matters: Where the damage occurs determines your symptoms. Damage to your optic nerve causes vision problems. Damage to your spinal cord causes numbness, weakness, or bladder issues. Damage to your brain affects balance, coordination, memory, or concentration ^[3].

The scarring pattern in MS is unique to each person, which explains why symptoms vary so much ^[5].

Patterns in MS

MS follows different patterns in different people. The main types that are discussed at diagnosi are:

Relapsing-Remitting MS (RRMS)

This is the most common type; about 85% of people initially diagnosed have RRMS ^[3]. You experience periods when new symptoms appear or existing ones worsen (relapses), followed by periods when symptoms improve or disappear (remission).

Relapses typically develop over a few days, last days to weeks, then gradually improve. You might have weeks, months, or even years between relapses.

Secondary Progressive MS (SPMS)

Many people with RRMS eventually develop SPMS. Research shows that approximately 60-70% of people with RRMS transition to SPMS within 20-25 years, though modern treatments are helping delay or prevent this ^[6].

With SPMS, symptoms gradually worsen over time rather than coming in distinct attacks. You may still have occasional relapses, but there’s underlying progression between attacks.

Primary Progressive MS (PPMS)

PPMS affects about 10-15% of people diagnosed with MS ^[3]. Symptoms gradually worsen from the beginning, without clear relapses and remissions. PPMS typically appears later in life (around age 40 or older) and affects men and women more equally, unlike RRMS which affects more women.

Understanding Progression: Beyond Relapses

Recent research has revealed that MS progression is more complex than we once thought.

We now know that disability can worsen in two main ways ^[12]:

Relapse-associated worsening (RAW): This is disability that develops during or after a relapse, when you don’t fully recover from an attack.

Progression independent of relapse activity (PIRA): This is when disability gradually gets worse without obvious relapses. It’s sometimes called “smouldering MS” because it reflects ongoing, low-level inflammation and nerve damage happening in the background ^{[12, 13]}.

PIRA can occur at any stage of MS, even early in relapsing-remitting disease ^[3]. Studies show that PIRA contributes significantly to disability accumulation, even in people whose relapses are well-controlled with medication ^{[13, 14]}. This happens because current MS medications primarily target the immune cells in the blood that cause relapses, but they’re less effective at stopping the chronic inflammation and nerve damage occurring deep within the brain and spinal cord ^[11].

This understanding is changing how doctors think about MS treatment. While controlling relapses remains crucial, researchers are now developing treatments that can get into the brain better and target these smouldering processes. Early trials of drugs called BTK inhibitors have shown promise in slowing this type of progression ^{[11, 12]}.

Understanding Your Outlook

While we can’t predict exactly how MS will affect you, understanding certain factors can help you and your neurologist make informed treatment decisions. Think of it like weather forecasting – we can give probabilities based on patterns, but can’t be certain about specifics.

Today’s disease-modifying therapies are changing outcomes for people with MS for the better^[4]. Early and effective treatment can help prevent progression, as well as factors that are within your control. Stopping smoking, maintaining a healthy weight, managing blood pressure and cholesterol, and staying physically and mentally active can all help improve your outlook ^{[8, 9]}.

Why Symptoms Vary So Much

One of the most challenging aspects of MS is its unpredictability. Two people with MS can have completely different experiences. Here’s why:

Location of damage: Your symptoms depend entirely on where damage occurs in your brain or spinal cord. Symptoms vary from person to person and may change in severity day to day ^[3].

Severity of damage: Some attacks cause significant myelin loss, while others are milder. Your body’s ability to repair damage also varies, affecting recovery from each relapse ^[3].

Individual differences: Your age when MS starts, genetics, overall health, and lifestyle all play a role. Research shows that smoking, and body weight influence disease progression ^{[8, 9]}.

Treatment effects: Newer disease modifying therapies can dramatically alter MS outcomes ^[4].

Time and progression: MS changes over time. Your symptoms might be quite different 10 years after diagnosis, regardless of which type you have.

Common Symptoms

While everyone’s experience is different, common symptoms include:

• Fatigue (often overwhelming and not related to activity levels)
• Vision problems (blurred vision, double vision, or temporary vision loss)
• Numbness and tingling (usually in face, arms, legs, or torso)
• Muscle weakness (making it harder to walk or use your hands)
• Balance and coordination issues
• Bladder and bowel problems
• Cognitive changes (difficulty with memory, concentration, or finding words)
• Pain (including nerve pain and muscle spasms)
• MS is different for everyone and no one can predict exactly how much it might affect you ^[3].

What Current Research Shows

Our understanding of MS has changed significantly over time. A comprehensive 2024 review found that early signs of MS, including depression, anxiety, fatigue, sleep problems, and headaches, can appear years before obvious symptoms ^[11].

New diagnostic tools are helping doctors identify MS earlier. The 2024 McDonald criteria revision has improved diagnostic accuracy, allowing earlier treatment ^[11].

Key Takeaways

MS is a complex condition where your immune system mistakenly attacks the protective coating around nerve fibres in your brain and spinal cord. This disrupts communication between your brain and body, causing varied symptoms.

Remember:

• MS affects more than 33,000 Australians, with particularly high rates in southern regions ^[1]
• Symptoms vary because nerve damage is unique to each person
• Newer treatments can significantly reduce relapses and slow progression, especially when started early ^[4]
• While we can’t predict your exact course, understanding key factors helps guide treatment decisions ^[7]
• Some factors that influence outcomes are within your control, stopping smoking, maintaining healthy weight, and staying active all help ^{[8, 9]}
• Understanding what MS is and how it affects your body is an important first step. This knowledge helps you work effectively with your healthcare team, make informed treatment decisions, and take steps to maintain your wellbeing.
• With the right support, treatment, and self-management, many people with MS continue living full, active, meaningful lives.

References

1. Campbell JA, Simpson-Yap S, Taylor BV, van der Mei I, Laslett L, Henson G, Zhao T, Palmer AJ. Significantly increasing multiple sclerosis prevalence in Australia from 2010 to 2021. Mult Scler. 2024 Aug;30(9):1113-1127. doi: 10.1177/13524585241265890.
2. Walton C, King R, Rechtman L, Kaye W, Leray E, Marrie RA, Robertson N, La Rocca N, Uitdehaag B, van der Mei I, Wallin M, Helme A, Angood Napier C, Rijke N, Baneke P. Rising prevalence of multiple sclerosis worldwide: Insights from the Atlas of MS, third edition. Mult Scler. 2020 Dec;26(14):1816-1821. doi: 10.1177/1352458520970841.
3. Haki M, AL-Biati HA, Al-Tameemi ZS, Ali IS, Al-hussaniy HA. Review of multiple sclerosis: Epidemiology, etiology, pathophysiology, and treatment. Medicine (Baltimore). 2024 Feb 23;103(8):e37297. doi: 10.1097/MD.0000000000037297.
4. Giovannoni G, et al. Brain health: time matters in multiple sclerosis. 2015, Oxford Health Policy Forum CIC. Available at: https://www.msbrainhealth.org/recommendations/brain-health-report/
5. Lassmann H. Pathogenic Mechanisms Associated With Different Clinical Courses of Multiple Sclerosis. Front Immunol. 2018;9:3116. doi: 10.3389/fimmu.2018.03116.
6. Klineova S, Lublin FD. Secondary Progressive Multiple Sclerosis: New Insights. Continuum (Minneap Minn). 2019 Jun;25(3):636-650. doi: 10.1212/CON.0000000000000727.
7. Miller DH, et al. Clinically isolated syndromes. Lancet Neurol. 2012: 11:157–69. doi: 10.1016/S1474-4422(11)70274-5.
8. Weld-Blundell IV, et al. Lifestyle and complementary therapies in multiple sclerosis guidelines: Systematic review. Acta Neurol Scand. 2022;145:379–92. doi: 10.1111/ane.13578.
9. Kappus N, et al. Cardiovascular risk factors are associated with increased lesion burden and brain atrophy in multiple sclerosis. J Neurol Neurosurg Psychiatry. 2016;87:181–7. doi: 10.1136/jnnp-2014-310051.
10. Ferreira-Atuesta C, Reyes S, Giovanonni G, Gnanapavan S. The Evolution of Neurofilament Light Chain in Multiple Sclerosis. Front Neurosci. 2021 Aug 19;15:642384. doi: 10.3389/fnins.2021.642384.
11. Multiple sclerosis: 2024 update. PLoS One. 2024 Jul 8;19(7):e0306006. doi: 10.1371/journal.pone.0306
12. Niedziela N, Adamczyk-Sowa M, Niedziela JT, Mazur G, Sowa P. Clinical and therapeutic challenges of smouldering multiple sclerosis. Neurol Neurochir Pol. 2024;58(3):260-270. doi: 10.5603/pjnns.98592.
13. Tur C, Moccia M, Barkhof F, et al. Assessing treatment outcomes in multiple sclerosis trials and in the clinical setting. Nat Rev Neurol. 2018;14(2):75-93. doi: 10.1038/nrneurol.2017.171.
14. Kappos L, Wolinsky JS, Giovannoni G, et al. Contribution of Relapse-Independent Progression vs Relapse-Associated Worsening to Overall Confirmed Disability Accumulation in Typical Relapsing Multiple Sclerosis in a Pooled Analysis of 2 Randomized Clinical Trials. JAMA Neurol. 2020;77(9):1132-1140. doi: 10.1001/jamaneurol.2020.1568.