What are the risks if you are not treated with a DMT?

Risks of no DMT

If you are an individual with MS, predicting what will happen to you is difficult. However, lots of studies monitoring groups of MSers show us patterns in the general progression of the condition. In general, the data is consistent. Briefly, given sufficient time, MSers who are not treated will become disabled. Most people focus on physical disability, but MS causes many hidden problems, such as cognitive impairment, anxiety and depression. The following slideshow gives you some of the headline facts. It's important to note that the outcomes in this slideshow are from the pre-DMT era and don't apply to populations of MSers treated with DMTs. New real life data indicates that DMTs, particularly high-efficacy DMTs, are preventing many of these problems. By not being on a DMT, if you have active MS, you are at risk of acquiring damage from focal inflammatory lesions. You may not be aware of this damage because of the remarkable capacity of the nervous system to compensate. However, once the compensatory mechanisms have been exhausted, further damage results in overt disability. It is important to think about DMTs as being preventive treatments, i.e. the aim of the treatments is to delay, and hopefully prevent, future disability.

Reasons for not being treated with a DMT

A large number of MSers will not be on a DMT, for many reasons, including:

1. They may have inactive MS and hence will not be eligible for a DMT. Please be aware that there is no standard definition of what active MS is. To me, active MS is recent evidence of focal inflammatory disease activity defined as: (a) clinical relapse(s) in the last 2 years or (b) MRI activity in the last 12 months (new or enlarging T2 lesions or T1 Gd-enhancing lesions) or (c) a raised CSF neurofilament light chain level in the last 12 months. Worsening disability without focal inflammatory disease activity is not active disease. Worsening disability in MS can be due to damage caused by past inflammation or the effects of premature ageing; anti-inflammatory DMTs can't address this problem. We need different types of DMTs to address these mechanisms, for example neuroprotective and/or remyelination therapies and anti-ageing therapies.
2. Family planning (trying to fall pregnant, pregnancy or breastfeeding); please note that most neurologists now have DMT options to treat MS during pregnancy so this is becoming less common reason to not be on a DMT.
3. Risk averse: some MSers are not prepared to take the risks associated with DMTs.
4. Personal reasons: some MSers don't believe in having their MS treated. It is not uncommon for some MSers to want to try alternative medicines and turn down traditional DMTs. If you are one of these people I would recommend you continue to interact with your MS team and have regular monitoring (clinical, MRI, PROMS and possibly CSF) of your MS so that if these alternative strategies don't work you keep the option open of being treated with a 'traditional DMT'. A lot of alternative treatment strategies for MS are not incompatible with DMTs and hence should be viewed as being complementary. Understanding the difference between complementary and alternative treatments is important. Complementary treatment strategies are part of the holistic management of MS.
5. Financial (not covered by a national health service or medical insurance scheme, or they can't afford DMTs).
6. Progressive or more advanced MS: in most countries neurologists don't initiate treatment in MSers with more advanced MS. The latter is based on a lack of evidence of the effectiveness of DMTs in this population. Please note that we are increasingly offering MSers with more advanced MS with active disease off-label therapies.
7. Ageism: some healthcare systems and some neurologists are reluctant to start DMTs in MSers who are over a certain age. Again this is based on a lack of evidence of the effectiveness of DMTs in this population. I personally don't agree with this. This is why we need to do clinical trials in older populations of MSers.