Most people have heard of MS, but few realise the name is actually an umbrella term for several different types of the disease.
The most common form of MS is relapsing–remitting MS or RRMS. Around 85% of people are initially diagnosed with this type of the disease, which is characterised by annoying flare ups of symptoms that come and go. These ‘relapses’ are then followed by periods of partial or complete remission when there might be no symptoms at all. You simply wake up one day and all is good with the world. Or at least it is until the next bout of weird and wonderful symptoms begin.
Understanding MS progression
Not only do the symptoms of RRMS vary from person to person, they tend to progress over time, too. The flare ups experienced by anyone with RRMS are caused by inflammation of the myelin sheath that surrounds the nerve fibres. Gradually, it seems the body loses the ability to repair the myelin, and the nerve fibre itself begins to undergo damage . This slow breakdown of the nerve fibres brings with it a gradual decline in nerve function, and a build-up in symptoms. You might notice, for example, that it takes you longer to finish the crossword, or that you can’t get around as easily as you used to. In fact, these changes are a natural part of ageing; it’s just that in people with MS things can be slightly accelerated . Once your condition shifts from the inflammatory phase of RRMS to the neurodegenerative one, doctors refer to it as secondary progressive MS or SPMS .
Keeping progression in perspective
If you have a chronic condition like MS, then of course the last thing you want to hear is the dreaded P word, but the term ‘progressive’ doesn’t always spell disaster – most of the time the word progressive is simply how doctors describe the pattern of symptoms. In fact, the transition from RRMS to SPMS is typically so gradual, doctors can usually only recognise SPMS after a year of altered symptoms and no relapses . In other words, you won’t just wake up one day and suddenly discover your MS is ‘worse’ – SPMS is simply a continuation of RRMS.
Some people have progressive MS from the outset. Primary Progressive MS (PPMS), for example, is diagnosed in around 10% of people with MS, with symptoms gradually worsening from the get go . With this type of MS, there are no relapses or periods of remission. Progressive-Relapsing MS (PRMS) is an even rarer form, with just 5% of people with MS affected. This type of MS is characterised by steadily worsening symptoms from the outset, with relapses but no remission.
For anyone with progressive MS, the lack of information can be frustrating. Until now, research has mostly focused on RRMS, since this is the most common form of the disease and, consequently, the most understood. This is also the reason that there are fewer treatment options for progressive forms of MS. The focus has always been on delaying or preventing the progressive phase – which makes sense but is no help whatsoever if you’re already knee deep in symptoms.
But things are changing. In the past it took around 20 years for RRMS to enter the secondary progressive phase, but now, thanks to the development of disease-modifying drugs, fewer people are developing SPMS in the first place, and those who do, take longer to get there.
And, of course, the more we understand about RRMS, the more researchers are able to apply this knowledge to more progressive types of the disease. In fact, thanks to the creation of the Progressive MS Alliance in 2012 , they’re making it a priority,. The hope is that by working together, the major MS research bodies around the world will be able to shed more light on progressive forms of MS and develop effective drugs that stop the disease in its tracks. See, not all ‘progress’ is bad.