Multiple Sclerosis Epidemiology Genetics, Environmental Factors Treatment Yvonne Benešová Department of Neurology Faculty od Medicine MU University Hospital Brno Multiple Sclerosis • Multiple sclerosis is a chronic, autoimmune demyelinating, degenerative disorder of the CNS – brain, spine, optic nerve – Typical sign of MS is repeating demyelinaition, disseminated in spase and time – Axonal degeneration – gliosis • Affects around 2.5 millions people • MS is the main cause of neurological disability in young people Multiple Sclerosis • Affects young people 20-40 years rarely children, after 60 • Mostly female – 2.5:1 • Incidence and prevalence in recent years increasing 1 • Autoimmune disease• SLE incidence 90% • 1Orton SM et al., Lancet Neurol , 2006 Multiple Sclerosis • MS is a multifactorial disorder • No single factor is responsible for conferring susceptibility • The aetiology is complex • Involving both environmental and genetic factors Multiple Sclerosis • Environmental factors • Evidence from geographical and migration studies has suggested that environmental factors play an important role in either increasing or decreasing the risk of MS in patients with a genetic susceptibility to the disease • Genetic factors • Population genetics and twin studies have shown how important the genes are in conferring susceptibility to MS • Involved 200 small genes Environmental factors • There is evidence for playing roles • both infection and the chemico-physical environment • infection, sunshine, vitamin D, geographical gradient, race, hormonal influence, stress • Additional data are needed to conclusively prove which factors are the most important in MS Geographical Distribution of MS • The prevalence of MS increases with lalitude • increasing from the equator • Prevalence in CR 150/100 000 inh • North USA, Canada and Europe 250-300/100 000 • South USA, Europe, Australia 50-100/100 000 Geographical Distribution of MS • Lowest risk Asia, Africa 5/100 000 • Latin America 29/100 000 Middle East • For the geographical distribution of MS, an environmental factors (relation infections, sunshine exposure, vitamin D) are a likely candidate Geographical Distribution of MS Prevalence Increases away from the Equator • Study in France confirms that MS prevalence shows a gradient increasing from the equator • in homogenous populations • 4 mil. farmers • S-N • 69% F Vukusic S et al. J Neurol Neurosurg Psychiat 2007;78:707–709. JNeurolNeurosurgPsychiat2007;78:707–9.Reproduced/amendedwith permissionfromtheBMJPublishingGroups 53 55 70 47 76 7178 51 53 51 59 77 88 103 97 100 84 93 87 95 62 82 World Health Organisation Atlas MS resources in the world 2008 World Health Organisation. Multiple sclerosis International Federation [on-line]. Atlas Multiple sclerosis resources in the world 2013. Dostupné z WWW: . World Health Organisation Atlas MS resources in the world 2013 World Health Organisation. Multiple sclerosis International Federation [on-line]. Atlas Multiple sclerosis resources in the world 2013. Dostupné z WWW: . The Effect of Migration on MS Prevalence • Individuals migrating after age of 15 have the risk of the country of origin • An environmental factor (an infectious agent acquired during infancy/puberty is plausible for the age-related migration effects, sunshine exposure, vitamin D) Population genetics • MS prevalence varies with ethnic ancestry: white populations are at greatest risk 1 (areas in which Nordic invasions took place) • Black population 0.5 risk • Oriental 0.1 risk • Racial differences may explain some of the geographic distribution differences Britain 200/100.000 Japan 1.4/100.000- Devic although both countries lie at the same latitude Genetics • Genetic factors contribute to the aetiology of MS It is not classic Mendelian type of heridity • Multiple small genes and their combination confer susceptibility for development of autoimmune process 1 200 • The first genetic investigations arised from higher occurence of MS in families • Ebers, G., 1995. Genetic factors in multiple sclerosis. MS Forum, Modern Management Workshop, Boston. Genetic susceptibility • Studies of families and twins provide suport • the life-time risk of developing MS is about 1/1000 in the general population • about 15% of patients with MS have an affected relative • children are at risk of about 5% • about 30% risk in monozygotic twins • 3-5% risk for same-sex dizygotic twins Twin Studies • High MZ versus DZ concordance rates reflect genetic factors • Concordance rates vary with background prevalence: – Canada, Denmark, Finland, UK, USA1 – France1 – Italy2 MZ = 25–30% DZ = 3–5% MZ = 5.9% DZ = 3% MZ = 14.5% DZ = 4% 1Willer CJ et al. PNAS 2003;100:12877–12882; 2Ristori G et al. Ann Neurol 2006;59:27–34. Cumulative Effect of Adding Shared Genes • Baseline population rate of 1/1000 – add in the risk of increasing gene sharing: – Cousin has MS 7/1000 – Paternal half-sibling 13/1000 – Maternal half-sibling 24/1000 – Full sibling 35/1000 – MZ twin (all genes are common) 270/1000 • DZ twins have a higher MS risk than full siblings • both share 50% of their genome • suggesting the role of gestational and environmental factors Ebers GC. Unpublished data. Genetics • Regions of interest in MS identified on all chromosomes, but only one confirmed1 • The major histocompatibility complex (HLA) on chromosome 6 has been identified as one genetic determinant for MS • Positive results for HLA Class I/II, T-cell receptor , IL7-R, IL2-R, and cytotoxic T-lymphocyteassociated protein 4 1Colhoun HM et al. Lancet 2003;361:865–872; 2Gregory SG, et al. Nat Genet 2007: published online: 29 July 2007. doi:10.1038/ng2103; 3Dyment DA et al. Lancet Neurol 2004;3:104–110. Genetics • I. and II. class HLA genes • play a key role in the autoimmune response and antigen presentation for CD4+ and CD8+ lymphycytes • I class genes (HLA-A, HLA-B, HLA-C) Presentation for CD8+ lymphycytes • II class genes (HLA-DP, HLA-DQ, HLA-DR) expression on B-, T-lymphocytes, macrophages • Short arm of the 6. chromosome-most polymorphic • Endode cell surface proteins • Play essential role in initiating an immune response • Presentation of antigens for CD8+, CD4+ ly • Gene map of the HLA region. Expert Reviews in Molecular Medicine 2003 Cambridge University Press, 2003, Cambridge University Press, 2003 HLA genes - I and II class HLA-associated Diseases Considerable data on HLA haplotype frequencies and autoimmune diseases DR2 DR3 DR4 DR4 B47 B27 0 50 100 MS CD RA IDDM CAH AS Phenotypefrequency coeliac disease; type 1 diabetes; congenital adrenal hyperplasia; ankylosing spondylitis Patients Healthy controls Genetics • Genome-wide association studies (GWAS) • International MS Genetic Consortium (IMSGC) • MS Genetics Group studies • It was proved association with DR2 haplotype in European population with MS – HLA-DRB1*1501-DQA1*0102-DQB1*0602 1-5 • Carriers of this haplotype have a 3-fold increased risk of developing disease, in homozygotes even 6-fold Genetics • Metaanalysis ass studies (GWAS) in group of 9.772 patients from Europe, 17.376 2013 • Data were made by 23 research groups 15 countries, 465 434 polymorfisms • Proved with HLA-DRB1*1501 risk allele • (p=1x10–320, OR=3.1) • Other populations Sweden- 61 % in MS compared to 31 % in control group • Other ethnic groups – Japan, Middle East • Protective effect HLA-A*02 class HLA I • It was proved next 101 suspect gene polymorphisms • 1 International Multiple Sclerosis Genetic Consortium: Sawcer S et al. Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis. Nature 2011; 10:214-9 Genetics • Non-HLA genes take part in the development and progression of the disease Several international studies • Proved significant association with gene polymorphisms for CD25 and CD 127 • encoding cytokines IL-7 and IL-2 • The whole genome of 931 families was examined International MS genetic consorcium 1 • Hafler et al., 2007 Genetics • It was proved association with MS HLA A 02 and DRB1 15 have 23 times increase risk for development of MS • Mutations in the genes encoding inflammatory proteins may influence the expression level as well as the stability of mRNA, which could influence the aetiopathogenesis of the MS process • Brynedal-2007 Genetics • Genes coding • Cytokines CXCR5, IL2RA, iL7R, IL7, IL12RB1, L22RA2, IL12A, • L12B, IRF8, TNFR • Costimulation molecules CD37, CD40, CD58, CD80, CD86, • CLECL1 • Signal molecules CBLB, GPR65,MALT1,TYK2 • Lack of genes take part in neurodegenerative process Environmental Factors • Infections • Sunshine and Vitamin D3 • Stress • Social and cultural factors Multiple Sclerosis Environmental Factors Infections Possible Candidate Microorganisms • Chlamydia • Herpesviruses – HHV-6 – HSV – CMV – EBV – Varicella zoster • Canine distemper virus • Measles virus • Rubella • HTLV-1 • HERV • Corona virus • Bordetella pertussis • Mumps virus Soldan SS et al. Nat Med 1997;3:1394–1397. Infectious Aetiology of MS Viruses all have been reported to be present in patients with MS Probable no single virus is the trigger for demyelination in all patients with MS Instead, several different viruses may be involved EBV and MS Risk – Epidemiological Evidence • EBV has a potential role in MS aetiology in many sero-epidemiology studies 1–8 • MS risk very low in people never infected with EBV2 – >99% of MS patients infected with EBV (~90% of controls)3 • Higher risk of developing MS following symptomatic EBV infection- mononucl. than if no prior history persists for 3 decades1 1Nielsen TR et al. Arch Neurol 2007;64:72–75; 2Thacker EL et al. Ann Neurol 2006;59:499–503; 3Ascherio A et al. Epidemiol 2000;11:220–224; 4Ascherio A et al. JAMA 2001;286:3083–3088; 5Levin LI et al. JAMA 2003;289:1533–1536; 6Levin LI et al. JAMA 2005;293:2496–2500; 7Sundstrom P et al. Neurology 2004;62:2277–2282; 8DeLorenze BN et al. Arch Neurol 2006;63:839–844; 9Munch K et al. Acta Neurol Scand 1998;98:395–399. Potential Mechanisms of EBV Involvement in MS • As-yet unknown mechanisms • Autoimmune – Molecular mimicry1,2 – Cross reactivation between antigens EBV and PLP • Oligodendrocyte infection – New symptomatic MS lesions contain evidence of extensive oligodendrocyte apoptosis 4 • Bystander activation B-lymfocytes infected by EBV express new antigen alfa B crysatllin, and lead secondary to T-lymphocyte activation 1Lang HLE et al. Nat Immunol 2002;3:940–943; 2van Sechel AC et al. J Immunol 1999;162:129–135; 3 Pender MP. Trends Immunol 2003;24:548–588; HHV-6 • Evidence to support HHV-6: – Increased titres of HHV-6 in MS – association controversial1–4 – HHV-6 showed a positive association in 29/37 MS studies5 – Positive association in 78% of studies (n=38) if active and latent virus differentiated6 1Sanders VJ et al. J Neurvirol 1996;2:249–258; 2Soldan SS et al. Nat Med 1997;3:1394–1397; 3Ablashi DV et al. Mult Scler 1998;4:490–496;4Ablashi DV et al. J Clin Virol 2000;16:179–191; 5Ablashi DV. http://www.hhv-6foundation.org/febpressrelease.pdf; 6HHV Foundation. www.hhv- 6foundation.org;7 Munger KL et al. Epidemiology 2003;14:141–147; 8Munger KL et al. Neurology 2004;62:1799–1803; 9Bagos PG et al. Mult Scler 2006;12:379–411. Multiple Sclerosis Environmental Factors Sunshine and Vitamin D3 Multiple Sclerosis Sunshine and Vitamin D3 • Vitamin D3 is very important environmental factor and a potent immunomodulator • Hypothesis of relationship between chronic vitamin D3 deficiency and increased risk for developing MS in definite geographic distribution is in relation with prevalence of this illness in temperate zone The Main Biological Effects of Vitamin D3 • Calcium homeostasis – Regulates Ca and phosphorus – Promotes bone formation and mineralisation • Vitamin D3 is a potent immune modulator – Enhances macrophage phagocytosis – Induces expression of cytokine IL-10 (anti inflammatory) – Inhibits production and function of Th1-inducing proinflammatory cytokines (IL-1) – Inhibits transcription of IFNγ target genes – Induces expression of antimicrobial peptides The Main Biological Effects of Vitamin D3 • Neuroprotection – Induces expression of nerve growth factor – Protects against reactive oxygen species-induced oxidative damage • Immune system regulation – Promotes immunosuppression, phagocytosis by macrophages, anti-tumour activity – vitamin D3 supplementation correlated with reduced risk of some cancers Sunshine and Vitamin D3 • Hypothesis of relation between chronic vitamin D3 deficiency and increased risk for developing MS in definite geografical distribution is in link with prevalence of this illness in temperate zonegeographical gradient • Insuficient production of vitamin D3 due to low sunlight exposure • Calcitrol - active metabolit of vit D3 strong EAE inhibitor suplementation to severe disabled mouse improvement of disability Biological Effects of Ultraviolet Radiation on Vitamin D3 • Vitamin D3 • Generated in skin when light energy is absorbed by a precursor molecule (7-dehydrocholesterol) • Inactive until converted to the hormonally-active form (1,25(OH)2D3) calcitrol 25-hydroxycholecalciferol (25-hydroxy vitamin D3) cholecalciferol (vitamin D3) HO 7-dehydrocholesterol HO 1,25-dihydroxycholecalciferol (1,25-dihydroxy vitamin D3) HO OH HO OH OH In liver In kidney In skin ACTIVE FORM Sunshine and Vitamin D3 Months/year when sunshine cannot produce sufficient vitamin D3 in the skin1–3 1Jablonski NG, Chaplin G. J Hum Evol 2000;39:57–106; 2Jablonski NG, Chaplin G. Scientific American 2002;287:74–81; 3Chaplin G. Am J Phys Anthropol 2004;125:292–302. No vit D for >6 m/y No vit D for >6 m/y No vit D for 1–6 m/y No vit D for 1–6 m/y Vit D all year Theoretical skin colour based on environmental variables1–3 CourtesyofSarahChen Prevalence of MS in Norway • Prevalence data for counties in Norway (/105): – A Finnmark1 (2003) >83 – B Troms1 (2003) >104 – C Nordland (1999) 106 – D Nord Trøndelag (1999) 164 – E Oppland2 (2002) 190 – F Hordaland (2003) 151 – G Oslo2 (2005) 154 • In Norway, MS prevalence does not rise with increasing latitude, unlike other northern European countries and the USA • Lower incidences of MS in coastal fishing areas than inland farming areas1 due to higher nutrition intake of vitamin D3 - fishing 1Kampman MT et al. J Neurol 2007;254:471-477. 2Personal communication. A B C D E F G Sunshine Implicated in Several Diseases Reduced sunlight exposure has been linked to rickets and possibly to: • Autoimmune diseases – MS – Rheumatoid arthritis – Type 1 diabetes • Cancer (other than skin cancers) • Seasonal Affective Disorder Holick MF. Am J Clin Nutr 2004;80:1678S–1688S. Vitamin D3 in Humans: Supplementation • Oral vitamin D3 supplementation should be given strong consideration • US Nutrition Guidelines: LOAEL for vitamin D3 in humans is 2000 IU/D – Probably too low 200 IU/D • The tolerable upper intake level for vitamin D3 should probably be raised from 2000 IU/D to 10 000 IU/D3 • Vieth R et al. Am J Clin Nutr 2007;85:649–650; 3Hathcock JN et al. Am J Clin Nutr 2007;85:6–18. Other factors • There is no evidence that MS is worsened by pregnancy • Should be advised against routine influenza vaccination • Surgery, anaesthesia, and lumbar punctures also have been implicated in MS, but controlled studies failed to show any relation Multiple sclerosis Stress • Stress is important factor for development and progression of MS • Play important role in activation of immune system • Nervous, immune a endocrine systems are influenced Multiple Sclerosis Genetics and Environmental Factors How could the various factors interact to cause MS Genetically susceptible individuals (HLA haplotype) Lack of sunlight or vitamin D3 during gestation and/or early life (latitude- or skin tone-related) Developmental alterations may result from deficiency in sunlight interfering with the maturation of the nervous and/or immune systems and the establishment of tolerance Tolerance breakdown precipitated by viral infections and non-specific immune stimulation (EBV?) Course of Multiple Sclerosis • Relapsing-remitting MS • 85% of patients – the MS begins with new clinical neurological signs • Activation of inflamation- attack, relaps 24 hours Complete remission of the first symptoms occurs frequently, but during next attacks remissions do not occur or are incomplete then neurologic disability increase gradually Follow clinical remision- months, years (1-2) Course of the disease • Relapsing -remitting (80-85%) • Primary progressive (10-15%) • Sec. chronic-progressive (30-40%) 15 years • Relapsing-progressive 3% Syptoms and signs • MS varies from benign, largely symptom-free disease to a rapidly progressive and disabling disorder • Clinical course extends for many decades in most cases • Rare are fatal within a few months of onset • The optic nerve, chiasm, brain stem, cerebellum, pyramidal tract and spinal cord, especially the lateral and posterior columns - are involved Syptoms and signs Retrobulbar neuritis, a common manifestation of MS-25%, is characterized by gradual decrease of visual acuity (1-2 weeks), resolve 4-6 weeks, residual impairment of color vision, dim … Atrophy of the optic nerve may not be associated with any fundoscopic abnormality 35 to 50% of patients with optic neuritis develop MS Visual field defects ranging from a unilateral scotoma or field contraction to homonymous hemianopia, a central scotoma is the most characteristic field loss Syptoms and signs Diplopia 15 %, VII, VIII Limb weakness is the most common sign, monoparesis, hemiparesis, 50 % qvadriparesis may be present, an asymmetric paraparesis Spasticity and ataxia increase the gait disturbance Slowly progressive spastic paraparesis is particularly in patients with late onset Dysarthria, gait ataxia, tremor, incoordination of the trunk or limbs Symptoms and sign • tremor of the head • urinary symptoms-urgent miction, incotinency • paresthesias and sensory impairment • Mental symptoms • Depression is more common than the euphoria • Fatigue- chronic 85% • Cognitive impairment • monosymptomatic onset is most common Disease course • Two processes- inflammation, neurodegeneration • In the beginning – predominate inflammation • Attack-relaps- activation of inflammation • Later – predominate neurodegneration • Cause of neurological disability Multiple sclerosis • Chronic inflammatory disorder of the CNS • Demyelination and axonal degeneration • White matter plaques in the brain periventricular regions brainstem, spinal cord, optic nerve • brain and spinal cord atrophy • various neurological symptoms • reversibile x irreversibilile neurological deficit Multiple sclerosis • White matter plaques • in the brain • Periventricular regions brainstem, spinal cord, optic nerve, juxtacortical • Brain and spinal cord atrophy • Various neurological symptoms Source: MRI scans provided by Department of Radiology University Hospital Brno. Patient with advanced demyelinating disease- Flair Dawson fingers. Patient with advanced demyelinating disease with typical periventricular lesions. Source: MRI scans provided by Department of Radiology University Hospital Brno. Multiple sclerosis- pathogenesis • Autoimmune response direct against CNS antigens (MBP, MOG, MAG) and secondary autoantigens • Activation and clonal expansion of T-cells CD-4+ and cytotoxic CD-8+ • Secrete immune mediatorscytokines,chemokines TNF, IFN, IL • Activation B-cells, synthethise antibodies • Activated T-cells, B-cells,microglia, macrophages migrate across BB barrier Multiple sclerosis- pathogenesis • Autoimmune response direct against CNS antigens (MBP, MOG,MAG) and secondary autoantigens • Recognition of ‘non-self’ antigen generally results in an immune response. • Similar aminoacid sequence as in viruses-herpetic, EBV .. Multiple sclerosis- pathogenesis • Inflammation is a major contributor to the formation of acute lesions destruction of myelin sheats axonal degeneration demage of oligodendrocytes • Degree of inflammation is in correlation with the extent of axonal loss • primarily axonal degeneration • Four patterns of active MS lesions Management • Course can be modified • No treatment completly stops the disease Approved therapies • Interferon β-1a -Rebif® Avonex®, Plegridy® (30ug i.m./weekly) • Interferon β-1b Betaferon® 0,25 mg every other day s.c. • Glatiramer acetate- Copaxone® 40 mg/D s.c. • Teriflunomide – Aubagio p.o. • Slow accumulation of neurologic disablity by 30-40%, reduction of number and the severity of clinical attacks, and increasing MRI lesions The first line therapy Drug Admin Dose Frequency Name INF beta- 1b s.c. 250 EOD Betaferon INF beta- 1a s.c. 22, 44 3 x weekly Rebif 22 Rebif 44 INF beta- 1a i.m. 30 1x weekly Every two weeks Avonex Plegridy Glatiramer acetát s.c. 40 3 x weekly Copaxone Indication criteria for the initiation of DMD therapy • CIS • RR-MS 2 attacks in the past year 3 attacks in the past 2 years • Attack treatment • methylprednisolonSolu-Medrol 3-5 grams • It reduces inflammation activity It will not affect the progression of the disease even with repeated administration • Interferon beta is an antiproliferative multifunctional cytokine • Complex immunomodulatory effect reduction of activation and penetration of autoaggressive T ly into the CNS reduction of proinflammatory cytokine production, interferon gamma increased production of anti-inflammatory cytokines It reduces the permeability of the blood-brain barrier Glatiramer acetate- Copaxone • Copolymer of four amino acids (glutamate, lysine, alanine, tyrosine) contained in the same ratio as MBP Autoaggressive ly bind to GA produce anti-inflammatory cytokines and produce neuroprotective BDNF • S.c. at a dose of 40 mg 3x week Total reaction - histamine, redness, shortness of breath, lasting a few minutes, local reactions Second line treatment • Patient treated with interferons or glatiramer acetate The persistent high activity of the disease • Tysabri-Natalizumab • Fingolimod- Gilenya • Tecfidera-Dimethyl fumarate • Ocrevus- Ocrelizumab • Mavenclad- cladribinum • Lemtrada-Alemtuzumab Natalizumab - Tysabri • Monoclonal antibody It binds to the adhesion molecule VLA-4 on the surface of white blood cells and blocks its binding to vascular endothelial cells Prevents white blood cells from penetrating into the CNS Reduces RR - up to 60% It slows the progression of disability Significantly reduces brain MR activity by up to 90% Natalizumab - Tysabri • It is given as monotherapy This highly effective treatment is unfortunately associated with the risk of developing Progressive Multifocal Leukoencephalopathy – PML • Unfortunately, at present, there are no screening tests that would allow a reliable measure of risk • Significant risk factors include duration of therapy Previous treatment with immunosuppressants The presence of ELISA antibodies detected in serum JC virus Natalizumab - Tysabri • Risk of developing PML Treatmen duration Anti-JCV Antibody Negative Anti-JCV Antibody Positive Immunosupressive therapy - Immunosupressive therapy + 1-24 months <1/1.000 2/1.000 25-48 months 4/1.000 11/1.000 FINGOLIMOD- GILENYA • It is a synthetic analog of myriocin, derived from Isaria Sinclair's mushroom It binds to four of the five subgroups of sfigosinephosphate receptors in the human body The S1P1 receptor is responsible for the immunomodulatory effect of Fingolimod Binding of this receptor on the surface of white blood cells leads to their reduced travel from the lymphatic tissue FINGOLIMOD- GILENYA • There is a significant reduction of MRI lesions lower annual RR up to 77% of patients are without an attack Second line treatment • Ocrelizumab- Ocrevus directed against CD 20 antigen on mature B cells, but not plasma cells • for non-Hodkin´s lymphoma and RA • fairly safe medication (market 2019) • i.v. infusions, 2 weeks apart, every 6 months • Alemtuzumab-Lemtrada AB against CD 52, antigen on most B and T ly (leukemia) • Cladribine- Mavenclad Generalized immunosupression • Corticosteroids • Methylprednisolon 1 g per day for 3-5 days • Medrol 4mg/day • Prednison 5 mg/day Generalized immunosupression • Azathioprine-modest effect • Mitoxantrone- immunosupressant (side effect cardiomyopathy, promyelocytic leukemia)- in rapidly progressive MS • Cyclophosphamide?? • Methotrexate-slight effect • Cyclosporine A (renal side effects) Symptomatic treatment • Fatigue: Amantadine 2x100 mg (Viregyt) • Spasticity: Baclofen, Sirdalud • Spastic blader: Spasmex, Ditropan • Amitriptyllin 25 mg • Antineuralgic treatment: Lyrica, Gabapentin Current treatment of RR-RS • Long-term treatment slow the progression of the disease • Treatment of acute attack of the disease • Disease modifying drugs - DMD Slow progression immunomodulatory and immunosuppressive effect • Anti-inflammatory effect Current treatment • At present, we have a range of therapeutic options in MS treatment. • These drugs have in particular an anti-inflammatory effect. Therefore, our primary goal remains the early diagnosis of MS, the earliest initiation of treatment and thus the prevention of the development of the neurodegenerative process. • To prevent the disability of the patients