Prevalence
In the UK, there are ~130,000 people diagnosed with MS overall, with 7,000 people newly diagnosed each year.1
85% of patients are initially diagnosed with RRMS2
Risk factors
Genetics
- The largest genetic risk factor is an allele from the HLA-DRB1 gene, HLA-DRB1*15:01, which confers a ~3-fold increased risk of MS vs absence of the allele3
Vitamin D
- MS incidence and prevalence increased with distance away from equator4
- This is thought to be due to the increased natural vitamin D production in those living nearer the tropics4
Epstein–Barr virus (EBV) infection
- A meta-analysis of 18 articles found the relative risk of MS was strongly associated with EBV5
Smoking
- Smoking is associated with an increased risk of developing MS6

Relapses
Ten leading symptoms experienced with MS relapse (N = 3,882)4
- Relapses coincide with focal CNS inflammation and demyelination, which are typically seen on MRI as white matter lesions7
- Symptoms typically evolve over days to two weeks, stabilise for one to two weeks and then improve over weeks8
- As MS can affect any region of the CNS, it can generate almost any neurological symptom9,10
Remission
- In most cases, there is substantial recovery (remission) from the first relapse – only 4% of patients show no improvement9
- Sensory, visual and brainstem relapses may be more likely to result in complete recovery, but visual and sensory pathways may also be particularly susceptible to recurrent damage9
Management
- The NICE guidance on RRMS management suggests a holistic multidisciplinary team (MDT) approach including:11
- Lifestyle advice
- Social care
- Symptom management
- DMTs
- It is now known that damage to the brain from MS begins right at the start of disease12
- Therefore, beginning treatment with a DMT early in the course of disease may improve long-term outcomes11

DMTs
- A range of treatment options are now available, so a key clinical question has become how intensively to begin treatment at disease onset13
- A high- vs moderate-efficacy treatment is associated with increased immunosuppression; however, early use of such a treatment may improve long-term relapse and disability outcomes13

CNS, central nervous system; DMT, disease-modifying therapy; HLA, human leukocyte antigen; MRI, magnetic resonance imaging; MS, multiple sclerosis; NICE, National Institute for Health and Care Excellence; RRMS, relapsing-remitting multiple sclerosis.
References
- MS Society UK. MS in the UK [online]. Available from: https://www.mssociety.org.uk/what-we-do/our-work/our-evidence/ms-in-the-uk [Last accessed: March 2021].
- Dobson R, Giovannoni G. Eur J Neurol. 2019;26(1):27–40.
- Olsson T, Barcellos LF, Alfredsson L. Nat Rev Neurol. 2017;13(1):25–36.
- Ascherio A, Munger KL. Semin Neurol. 2016;36(2):103–114.
- Handel AE, Williamson AJ, Disanto G, et al. PLoS One. 2010:1;5(9):e12496.
- Hernán MA, Jick SS, Logroscino G, et al. Brain. 2005;128(Pt 6):1461–1465.
- Dendrou CA, Fugger L, Friese MA. Nat Rev Immunol. 2015;15(9):545–558.
- Palace J. J Neurol Neurosurg Psychiatry. 2001;71 Suppl 2(Suppl 2):ii3–ii8.
- Joy JE, Johnston RB Jr. (Eds.). Multiple sclerosis: Current status and strategies for the future [online] 2001. Washington DC, US: National Academies Press. 2001. Available from: https://www.ncbi.nlm.nih.gov/books/NBK222386/ [Last accessed: March 2021].
- Nazareth TA, Rava AR, Polyakov JL, et al. Mult Scler Relat Disord. 2018;26:219–234.
- NICE. Managing multiple sclerosis. Available from: https://pathways.nice.org.uk/pathways/multiple-sclerosis#path=view%3A/pa... [Last accessed: March 2021].
- Cerquiera JJ, Compston DAS, Geraldes R, et al. J Neurol Neurosurg Psychiatry. 2018;89(8):844–850.
- Stankiewicz JM, Weiner HL. Neurol Neuroimmunol Neuroinflamm. 2019;7(1):e636.