152 DOI: 10.1590/0004-282X20130252 guidelineS Supplementation and therapeutic use of vitamin D in patients with multiple sclerosis: Consensus of the Scientific Department of Neuroimmunology of the Brazilian Academy of Neurology Suplementação e uso terapêutico de vitamina D nos pacientes com esclerose múltipla: Consenso do Departamento Científico de Neuroimunologia da Academia Brasileira de Neurologia Doralina Guimarães Brum1, Elizabeth Regina Comini-Frota2, Claúdia Cristina F. Vasconcelos3, Elza Dias-Tosta4 1Departamento de Neurologia, Psicologia e Psiquiatria, Faculdade de Medicina de Botucatu, Universidade Estadual Paulista, Botucatu SP, Brazil; 2Hospital das Clínicas, Universidade Federal de Minas Gerais, Belo Horizonte MG, Brazil; 3Universidade Federal do Rio de Janeiro, Rio de Janeiro RJ, Brazil; 4Hospital de Base do Distrito Federal, Brasília DF, Brazil. Correspondence: Doralina G. Brum. Departamento de Neurologia, Psicologia e Psiquiatria da Faculdade de Medicina de Botucatu, Universidade Estadual Paulista - UNESP. Distrito de Rubião Júnior, s/n; 18618-970 Botucatu SP, Brasil. E-mail: dbrum@fmb.unesp.br Conflict of interest: The Brazilian Academy of Neurology (ABN) is committed to produce clinical guidelines critically and independently. This guideline is part of ABN’s continuing education activity. It is based on review of scientific and clinical knowledge. Its purpose is not to address the subject in its entirety. Treatment decision is shared between patient and physician and according to each situation. Support: This guideline was developed with financial support from the Brazilian Academy of Neurology. None of the authors received honoraria for their participation. The conflict of interest form for the issue specifically addressed in this article was signed by all authors. List of contributors: Amilton Antunes Barreira, Antônio Pereira Gomes Neto, Cláudio Roberto Carneiro, Carlos Augusto de Albuquerque Damasceno, Daniel Lima Varela, Damácio Rámon Kaimen-Maciel, Denis Bernardi Bichuetti, Denise Sisterolli Diniz, Eber Castro Correa, Elizabeth Batista da Silva, Fabio Siquineli, Fernando Coronetti Gomes da Rocha, Felipe von Glehn Silva, Fernando Faria Andrade Figueira, Gutemberg Augusto Cruz dos Santos, Heloise Helena de Figueiredo Siqueira, Jefferson Becker, Leandro Cortoni Calia, José Mauricio Godoy Barreiros, Luiz Domingos Mendes Melges, Marcos Aurélio Moreira, Marcos Papais-Alvarenga, Maria Cecília Aragon de Vecino, Maria Cristina Brandão de Giacomo, Maria Fernanda Mendes, Maria Lúcia Brito Ferreira, Maria Lúcia Vellutini Pimentel, Monica Koncke Fiuza Parolin, Nívea de Macedo Oliveira Morales, Osvaldo J.M. do Nascimento, Paulo Pereira Christo, Regina Maria Papais Alvarenga, Renata Brandt de Souza, Renato Puppi Munhoz, Rogério de Rizo Morales, Sidney Gomes, Solange Maria das G. G. Camargo, Soniza Vieira Alvez-Leon, Suzana Costa Nunes Machado, Tarso Adoni, Thereza Cristina D`Avila Winckler, Thiago de Faria Junqueira, Yara Dadalti Fragoso, and Yuna de Ribeiro Araújo. External collaborators: Alessandro Farias (researcher), Eduardo Antônio Donadi (immunologist), and Marcelo de Paula Corrêa (meteorologist). Received 10 January 2014; Accepted 20 January 2014. ABStrACt Multiple sclerosis (MS) is an inflammatory, autoimmune, demyelinating, and degenerative central nervous system disease. Even though the etiology of MS has not yet been fully elucidated, there is evidence that genetic and environmental factors interact to cause the disease. Among the main environmental factors studied, those more likely associated with MS include certain viruses, smoking, and hypovitamino- sis D. This review aimed to determine whether there is evidence to recommend the use of vitamin D as monotherapy or as adjunct therapy in patients with MS. We searched PUBMED, EMBASE, COCHRANNE, and LILACS databases for studies published until September 9th, 2013, using the keywords “multiple sclerosis”, “vitamin D”, and “clinical trial”. There is no scientific evidence up to the production of this consensus for the use of vitamin D as monotherapy for MS in clinical practice. Keywords: vitamin D, multiple sclerosis, experimental autoimmune encephalitis. reSumo A esclerose múltipla (EM) é uma doença inflamatória, autoimune, desmielinizante e degenerativa do sistema nervoso central. Estudos epi- demiológicos têm identificado associações de hipovitaminose D com doenças autoimunes. O principal objetivo desta revisão é responder se há evidências que indiquem o uso terapêutico de vitamina D em monoterapia para pacientes com EM. Por meio dos sites PUBMED, EM- BASE, LILACS e Scielo foram realizadas buscas usando os descritores “vitamin D”, e “multiple sclerosis” até 12/09/2013. Estudos clínicos randomizados, controlados e duplo-cegos foram selecionados para avaliar a resposta terapêutica da vitamina D na EM. Não foram encon- tradas evidências científicas que justifiquem o uso da vitamina D em monoterapia no tratamento da EM, na prática clínica. Palavras-chave: Vitamina D, esclerose múltipla, encefalite autoimune experimental. mailto:dbrum@fmb.unesp.br 153Doralina Guimarães Brum et al. Vitamin D and multiple sclerosis The therapeutic use of vitamin D for treating multiple scle- rosis (MS) is a controversial issue that is of interest to physi- cians, researchers, and patients. The Scientific Department of Neuroimmunology (DCNI) of the Brazilian Academy of Neurology (ABN) organized a meeting on September 12, 2013, to discuss the basic aspects of vitamin D metabolism, results of in vitro and experimental studies on experimental autoim- mune encephalomyelitis (EAE), and controlled clinical trials of vitamin D in MS. Neurologists and researchers participating in the meeting approved a guideline consensus to guide Brazilian neurologists in the care of patients with MS. VItAmIN D, mS, AND eAe Vitamin D is an important hormone for calcium homeo- stasis and bone metabolism1. Besides its action in bone tis- sue, vitamin D has a role in cell differentiation, cell growth in- hibition, and immune system modulation2. The main source of vitamin D is ultraviolet-B radiation (95%). However, no consensus has been reached on optimal serum vitamin D lev- els for human metabolic needs3,4. The association between vi- tamin D and autoimmune diseases and neoplasms has been established in recent years5, but this relationship has not yet been fully elucidated. Multiple sclerosis is an inflammatory, autoimmune, de- myelinating, and degenerative central nervous system (CNS) disease, whose geographic and ethnic distribution is charac- terized by a higher prevalence in northern hemisphere coun- tries, particularly in populations of Caucasian origin6. The predominantly temperate climate in the northern hemisphere with long periods of low solar radiation and the relatively high prevalence of hypovitaminosis D observed in population studies7 have led to the hypothesis that this de- ficiency may explain the geographical distribution of MS. Moreover, it has been suggested that adequate serum levels of vitamin D could help reduce the risk of developing MS8,9. Even though the etiology of MS has not yet been fully elu- cidated, there is evidence that genetic10,11 and environmen- tal12 factors interact to cause the disease. Among the main environmental factors studied, those more likely associat- ed with MS include certain viruses13, smoking14, and hypo- vitaminosis D15,16. The latter is particularly important in the northern hemisphere, where the seasonal variation and sub- sequent reduction in ultraviolet-B radiation in winter may lead to a higher prevalence of hypovitaminosis D. Some con- ditions represent risk of hypovitaminosis D in the general population such as long stay indoors, use of sunscreen, and skin pigmentation17,18. Motor limitations associated with lat- er stages of MS may contribute to the occurrence of hypovi- taminosis D in this group of patients19. Unlike northern hemisphere countries, solar radiation in Brazil is believed to be plentiful in all seasons and regions to prevent hypovitaminosis D. Thus, the amount of sunlight one is exposed in Brazil should be enough to avoid hypovitamin- osis D in healthy individuals when exposed to sunlight even for short periods. Nevertheless, no studies have compared se- rum vitamin D levels among Brazilian regions, whereas few studies have analyzed serum vitamin D levels in a selected risk group20. Preliminary experimental studies have demonstrated an immunomodulatory role of vitamin D on human im- mune cells in vitro21,22 and in an experimental animal model (EAE)23,24. An in vitro study with peripheral blood cells of pa- tients on vitamin D therapy showed that serum levels above 40 ng/ml may exert modulatory action on immune cells20. Additional studies are underway to better understand this immunomodulatory effect on autoimmune diseases. This review aimed to determine whether there is evi- dence to recommend the use of vitamin D as monothera- py or as adjunct therapy in patients with MS. We searched PUBMED, EMBASE, COCHRANNE, and LILACS databases for studies published until September 9th, 2013, using the key- words “multiple sclerosis”, “vitamin D”, and “clinical trial”. Randomized controlled clinical trials with vitamin D in pa- tients with MS were included in the analysis. rANDomIZeD AND CoNtroLLeD CLINICAL trIALS WItH VItAmIN D IN tHe treAtmeNt oF mS To evaluate the therapeutic response of vitamin D in MS patients, we selected double-blind, randomized, controlled clinical trials from the literature25,26-28. These studies are still scarce and most were not designed to evaluate therapeutic response to vitamin D. Next, we discuss the most relevant studies. A clinical study conducted in Finland25 in 66 patients with relapsing-remitting multiple sclerosis (RRMS) compared a group with 34 patients using 20,000 IU/week of vitamin D and interferon beta-1b (IFNβ-1b) to another group with 32 patients using IFNβ-1b only. In that study, primary outcomes included tolerability and safety aspects, and number of new lesions and gadolinium enhancing lesions on MRI scans. Secondary outcomes included clinical parameters such as annual relapse rate and changes in the Expanded Disability Scale Score (EDSS), in addition to other imaging parameters. The authors observed that the treated group showed fewer new T2 lesions, but there were no significant differences in clinical parameters between the two groups after 12 months. However, there was a significant reduction in the number of gadolinium enhancing lesions in the vitamin D group. Another study, conducted in Norway26, compared bone mineral density, relapse frequency, disease progression, and motor function measures between 35 patients with MS us- ing 20,000 IU of cholecalciferol per week associated with 500 154 Arq Neuropsiquiatr 2014;72(2):152-156 mg/day of calcium and a control group of 33 patients with MS using 500 mg/day of calcium only for two years26. Patients in both groups had been previously using immunomodula- tory drugs (interferon beta or glatiramer acetate) for a simi- lar period of time. No differences in annual relapse rate and changes in functional capacity measured by EDSS were ob- served between the two groups, even though vitamin D levels ranged from 24.72 ng/ml in the placebo group to 49.26 ng/ml in the vitamin D group. The study was not powered to ad- dress clinical outcomes12. A phase II study developed in Iran27 compared 25 patients with RRMS receiving the active form of vitamin D (calcitri- ol) at a dose of 0.25 µg/day with patients receiving placebo27. Both groups used conventional immunomodulators. There was no difference in the EDSS between the calcitriol and pla- cebo groups after 12 months followup13. It should be noted in that study the small sample size and inclusion criterion of serum 25-hydroxyvitamin D level >40 ng/ml. A randomized study in Australia28 compared 11 patients with RRMS treated with vitamin D2 in a dose of 6,000 IU twice daily in addition to a daily low-dose (1,000 IU) with 12 patients receiving the 1,000 IU/day dose only28. The neuraxi- al index of inflammatory activity on MRI was compared be- tween the high-dose and low-dose groups. No significant dif- ferences between the groups were detected. A meta-analysis of the studies cited above detect- ed no difference in the number of relapses between the groups29. The number of new lesions and gadolinium en- hancing lesions were compared to serum vitamin D levels in other two studies and the findings were conflicting26,30. Limitations of the studies include different dosages and forms of vitamin D administered. In contrast to epidemiological and experimental studies, randomized trials on the use of vitamin D in MS showed no significant differences in the parameters of disease activity – relapse rate, EDSS progression, and new or gadolinium en- hancing lesions on MRI – between the group receiving vita- min D and groups receiving placebo or a smaller dose of vi- tamin D. These differences and other contradictions indicate the need to conduct double-blind, randomized, controlled trials in large groups of patients, considering the differences between clinical, neuroimaging, biological, and immunologi- cal variables, and powered to accurately estimate the thera- peutic efficacy and possible side effects of vitamin D in MS. VItAmIN D AND otHer ISSueS Normal range The Institute of Medicine (IOM) and the American Society for Endocrinology advocate different levels of vita- min D to maintain bone health: ≥20 ng/ml and ≥30ng/ml, respectively3,4. There is no consensus on whether bone cells and immune cells require different levels of vitamin D. In ad- dition to the lack of consensus on the normal range values for vitamin D, the toxic serum concentration and the concen- tration leading up to this condition are also controversial. In adults, doses greater than or equal to 10,000 IU/day are asso- ciated with hypercalcemia31,32. High performance liquid chromatography (HPLC) fol- lowed by mass spectrometry is considered the gold stan- dard for analysis of serum 25-OH vitamin D levels. However, the technique is laborious, expensive, and is not available in most Brazilian laboratories. Other methods such as chemilu- minescence, enzyme immunoassay, and radioimmunoassay are also used. Thus, variability in results can occur depending on the assay used33. In Brazil, there is no efficient inter-labo- ratory validation system, which can also result in great vari- ability in results. Moreover, certain medications such as anti- convulsants and corticosteroids may have a role in reducing serum levels of vitamin D. SAFety proFILe The safety profile of different serum vitamin D levels has been evaluated in an open, randomized study conducted in Canada31. In that study, a group of 25 patients with MS used escalating cholecalciferol (vitamin D3) doses up to 40,000 IU/day, whereas a second group of 24 patients used 4,000 IU/day. Patients in both groups used immunomodula- tors (interferon beta and glatiramer acetate) in combination with cholecalciferol. The maximum 40,000 IU/day dose was used for up to six months, followed by 10,000 IU/day for three months and gradual suspension over three months. Both groups received calcium (1,200 mg/day) throughout the trial, and serum calcium was determined. Serum 25-hydroxivita- min D (25-OH-vitamin D) reached a maximum mean above 250 nmol/l (100ng/ml) during the 40,000 IU/day dosing peri- od. No hypercalcemia was detected during the 10,000 IU/day dosing period, even with serum levels ≥ 100 ng/ml, suggest- ing that that dose is safe (Class level II evidence). In addi- tion, neither serum calcium nor parathormone urinary levels were altered, even when serum concentrations were higher. Further studies are needed to confirm these findings. VItAmIN D – SIDe eFFeCtS Clinical picture of vitamin D intoxication may include signs and symptoms originating in different systems: nau- sea and vomiting, anorexia, abdominal pain, constipation; polydipsia, polyuria, dehydration, nephrolithiasis, nephro- calcinosis, nephrogenic diabetes insipidus, chronic inter- stitial nephritis, acute and chronic renal failure; hypotonia, 155Doralina Guimarães Brum et al. Vitamin D and multiple sclerosis paresthesia, confusion, seizures, apathy, coma; arrhythmia, bradycardia, hypertension, cardiomyopathy; muscle weak- ness, calcification, osteoporosis; and conjunctival calcifica- tion34-36. Hypercalcemia is the most important side effect, and when observed in the laboratory is suggestive of intoxication37. During use of vitamin D, in addition to serum calcium, urinary calcium should be assayed periodically. Serum con- centration of parathyroid hormone (PTH) should also be de- termined and must not exceed the lower reference values of normality indicative of suppression, which is a non-recom- mended condition35. FINAL CoNSIDerAtIoNS Considering the body of information presented here, the DCNI/ABN defines the consensus that: 1. It is recommended to dose vitamin D in patients with clinically isolated syndrome and MS, regardless of the stage of disease, particularly those making frequent use of corticosteroids or anticonvulsivants. 2. Peripheral blood levels of vitamin D lower than 30ng/ml should be corrected in patients with MS, at any stage, or in patients with demyelinating isolated syndrome (grade D recommendation). 3. Peripheral blood levels of vitamin D higher than 100 ng/ml should be avoided until new guidelines are established (grade D recommendation). 4. There is no scientific evidence up to the produc- tion of this consensus for the use of vitamin D as monotherapy for MS in clinical practice. Therefore, currently, vitamin D monotherapy for MS is considered experimental. For its use in clinical trials, these must be approved by the Human Research Ethics Committee, reg- ulated by the National Commission for Ethics in Research (CONEP), approved by the Regional Medical Board, and informed consent should be provided by patients. 5. According to data from in vitro studies with peripher- al blood cells of patients using vitamin D, serum levels above 40 ng/ml are likely to cause modulating action on immune cells17. Based on that evidence, vitamin D supple- mentation at doses that maintain serum levels of patients between 40 ng/ml and 100 ng/ml may be recommended, as these are safe levels (grade D recommendation). 6. Considering the individual differences in replace- ment needs and serum levels of vitamin D, that a study in healthy subjects showed that 5,000 IU/day of vita- min D for 15 weeks increased serum levels up to 60ng/ ml, and that doses up to 10,000 IU/day were considered safe, we recommend individualized doses until reach- ing serum levels between 40 ng/ml and 100 ng/ml (grade D recommendation). 7. Considering that low vitamin D serum levels in patients with isolated demyelinating syndrome could affect the relative risk of conversion to MS16, we recommend the analysis of serum vitamin D levels in those patients and that a correction is made whenever necessary (grade D recommendation). 8. Because vitamin D3 is a secosteroid hormone, its use should be escalated. Moreover, monitoring serum 25-hy- droxivitamin D would be extremely important before in- creasing dosage to determine whether supplementation is actually effective (grade D recommendation). Acknowledgments We thank the contributors who performed critical re- view of the manuscript: Amilton Antunes Barreira, Danilo Lima Varela, Denis B. Bichuetti, Felipe von Glehn, Eduardo Antônio Donadi, Gutemberg Augusto Cruz dos Santos, Marcos Papais-Alvarenga, Maria Fernanda Mendes, Maria Cecilia Vecino, Maria Lúcia Vellutini, Paulo Pereira Christo, Thiago Faria Junqueira, Soniza Vieira Alvez Leon, and Yara Dadalti Fragoso (Fragoso, YD). We also thank the invaluable expert assistance of Paulo S. Moraes Júnior in using Microsoft Lync for support in the online meeting. This manuscript was reviewed by a professional science editor and by a native English-speaking copy editor to im- prove readability. References 1. Grant WB, Holick MF. Benefits and requirements of vitamin D for optimal health: a review. Altern Med Rev 2005;10:94-111. 2. Bikle DD. Vitamin D regulation of immune function. Vitam Horm 2011;86:1-21. 3. Holick MF, Binkley NC, Bischoff-Ferrari HA, et al. 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