Prevalence Rate Of Multiple Sclerosis Research Articles

Prevalence and Burden of Multiple Sclerosis in China, 1990-2019: Findings From the Global Burden of Disease Study 2019.

Multiple sclerosis (MS) is the leading cause of neurologic disability in young adults, but the burden caused by MS in China is lacking. We aimed to comprehensively describe the prevalence and health loss due to MS by demographic and geographical variables from 1990 to 2019 across China. Data were obtained from the Global Burden of Diseases, Injuries, and Risk Factors Study 2019 (GBD 2019). We used GBD methodology to systematically analyze the prevalence, disability-adjusted life-years (DALYs), years of life lost (YLLs), and years lived with disability (YLDs) due to MS by age, sex, and location from 1990 to 2019 in mainland China and its provinces. We also compared the MS burden in China with the world and other Group of 20 (G20) countries. In 2019, 42,571 (95% uncertainty interval [UI] 33,001-53,329) individuals in China had MS, which doubled from 1990. The age-standardized prevalence rate of MS was 2.32 per 100,000 (95% UI 1.78-2.91), which increased by 23.31% (95% UI 20.50-25.89) from 1990, with most of the growth occurring after 2010. There was a positive latitudinal gradient with the increasing prevalence from south to north across China. The total DALYs caused by MS were 71,439 (95% UI 58,360-92,254) in 2019, ranking China third among G20 countries. Most of the MS burden in China derived from premature mortality, with the higher fraction of YLLs than that at the global level and most other G20 countries. From 1990 to 2019, the age-standardized DALY and YLL rate had nonsignificant changes; however, the age-standardized YLD rate substantially increased by 23.33% (95% UI 20.50-25.89). The geographic distribution of MS burden varied at the provincial level in China, with a slight downward trend in the age-standardized DALY rates along with increasing Socio-Demographic Index over the study period. Although China has a low risk of MS, the substantial and increasing prevalent cases should not be underestimated. The high burden due to premature death and geographic disparity of MS burden reveals insufficient management of MS in China, highlighting the needs for increased awareness and effective intervention.

Epidemiology and Healthcare Utilization in Pediatric Multiple Sclerosis and Neuromyelitis Optica: A Nationwide Population-Based Study in South Korea (2016-2020).

Pediatric multiple sclerosis (MS) and neuromyelitis optica (NMO) are rare acquired demyelinating syndrome with limited epidemiological data available, particularly in non-Western setting. This study aimed to demonstrate the epidemiology of pediatric MS and NMO in South Korea and to analyze of healthcare utilization and economic burden associated with these conditions. Using a nationwide population-based database from the Korean Health Insurance Review and Assessment Service database, we identified pediatric cases (age < 20 years) of MS and NMO from 2016 to 2020. We analyzed incidence, prevalence, healthcare utilization and medical costs. The study found low age-standardized incidence and prevalence rates for pediatric MS and NMO in South Korea. There was a marked disparity in healthcare utilization between urban and rural areas. Most healthcare interactions occurred in tertiary hospitals in urban settings, particularly in Seoul. The study also highlighted the substantial economic burden associated with the management of rare diseases, with annual variability in medical costs. Pediatric MS and NMO are extremely rare in South Korea, with significant regional disparity in healthcare utilization. The findings emphasize the need for targeted healthcare policies to improve access and reduce disparities, particularly for chronic and rare diseases requiring specialized care.

Prevalence, Incidence, and Mortality of Multiple Sclerosis in Coimbra, Portugal

Multiple sclerosis (MS) is the most common chronic inflammatory, demyelinating, and neurodegenerative disease of the central nervous system in young adults, representing the leading cause of nontraumatic disability in this population. The rising prevalence of MS worldwide makes it critical to recognize the absolute number of patients with MS, demanding the execution of a sustainable healthcare policy. In Portugal, only six studies evaluating MS rates were published, disclosing a prevalence of 64 cases per 100,000 persons and an incidence of 3.1 cases per 100,000 persons/year, but the mortality rates have not been reported. Thus, this observational, cross-sectional study aimed to assess MS prevalence, incidence, and mortality in the city of Coimbra, a region in the center of Portugal. Patients who fulfilled McDonald’s Diagnosis Criteria (2017) for MS were recruited. Inclusion criteria were defined according to prevalence, incidence, and mortality studies. The baseline demographic and clinical characterization of the prevalence study population was performed. The MS prevalence rate in Coimbra was 143.45 cases per 100,000 inhabitants. Between 2018 and 2021, the cumulative incidence was 8.52 new cases per 100,000 persons/year. The mortality rate between 2018 and 2021 was 2.84 deaths per 100,000 inhabitants. MS prevalence and incidence in Coimbra are higher than reported in previous similar studies and comparable to Europe’s mean prevalence and incidence.

What do animal models tell us about the role of EBV in the pathogenesis of multiple sclerosis?

Multiple sclerosis (MS) is a chronic disease of the central nervous system (CNS), marked primarily by demyelination, inflammation, and neurodegeneration. While the prevalence and incidence rates of MS are on the rise, the etiology of the disease remains enigmatic. Nevertheless, it is widely acknowledged that MS develops in persons who are both genetically predisposed and exposed to a certain set of environmental factors. One of the most plausible environmental culprits is Epstein-Barr virus (EBV), a common herpesvirus asymptomatically carried by more than 90% of the adult population. How EBV induces MS pathogenesis remains unknown. A comprehensive understanding of the biology of EBV infection and how it contributes to dysfunction of the immune system and CNS, requires an appreciation of the viral dynamics within the host. Here, we aim to outline the different animal models, including nonhuman primates (NHP), rodents, and rabbits, that have been used to elucidate the link between EBV and MS. This review particularly focuses on how the disruption in virus-immune interaction plays a role in viral pathogenesis and promotes neuroinflammation. We also summarize the effects of virus titers, age of animals, and route of inoculation on the neuroinvasiveness and neuropathogenic potential of the virus. Reviewing the rich data generated from these animal models could provide directions for future studies aimed to understand the mechanism(s) by which EBV induces MS pathology and insights for the development of prophylactic and therapeutic interventions that could ameliorate the disease.

Epidemiologic trends of multiple sclerosis in Puerto Rico (2013–2020)

BackgroundPrevious studies have demonstrated higher multiple sclerosis (MS) incidence and prevalence in Puerto Rico (PR) than in other Caribbean and Latin American countries. Our objectives are to update the epidemiologic trends in MS incidence and prevalence rates for PR from 2017 through 2020 and compare them to prior rate data from 2013 to 2016. MethodsWe used the Puerto Rico MS Foundation's registry (PRMS Registry) data to identify all newly diagnosed MS cases between January 2017 and December 2020. The study population included 568 MS patients, 406 women and 162 men living in PR. All individuals were 18 years and older and met the 2017 revised McDonald criteria for MS diagnosis. In addition, age- and sex-standardized incidence rates were estimated. ResultsA total of 568 new MS cases were diagnosed in Puerto Rico between 2017 and 2020. The 2020 MS cumulative prevalence for Puerto Rico was 95.3/100,000 (95% CI: 91.6, 99.1), higher than previously reported. The age- and sex-standardized MS incidence rate for Puerto Rico decreased from 6.5/100,000 (2017) to 6.3/100,000 (2020). The annual age-standardized MS incidence rates declined for females: from 9.5/100,000 (2017) to 8.2/100,000 (2020) but increased for males from 3.6/100,000 to 4.6/100,000 during the same period. ConclusionThese incidence and prevalence rates are among the highest reported among Caribbean and Latin American countries. A peak in the age- and sex-standardized MS incidence rate was observed after hurricane María (2018) and a decline during the first year of the COVID-19 pandemic (2020). Further investigation is needed to determine whether there was a causal relationship between the fluctuations observed and those natural events.

Interdependency of NINJ2 gene expression and polymorphism with susceptibility and response to interferon beta in patients with multiple sclerosis

Objective Multiple sclerosis (MS) is a multifactorial inflammatory and autoimmune condition that lead to chronic neurodegeneration and central nervous system (CNS) demyelination that mainly affects young adults. The incidence and prevalence rate of MS considerably vary in ethnicities and geographic regions and affecting women more than men. Interferon-β (IFN-β) is the first-line disease management for MS, while the majority of affected members does not respond to the IFN-β. Numerous recent studies shown a significant relationship between genetic variations and responsiveness to the IFN-β. Therefore, determining the genetic differences in the drug response could help determine precise treatment strategies. Methods The genotyping of the rs7298096 polymorphism (SNP) and NINJ2 gene expression were assessed in 99 responders and 106 non-responder patients with IFN-β treated RRMS. Results The distribution of rs7298096 SNP was significantly different in the responders and non-responder patients and the NINJ2 gene expression considerably increased in the non-responder patients compare to the responders. The NINJ2 gene expression level in the AA genotype of the non-responder group was higher than to the other genotypes of both groups. Conclusion Our results showed that the NINJ2 gene expression level and rs7298096 genotype possibly affect the response to the IFN-β in patients with RRMS.

Temporal Incidence and Prevalence Trends of Multiple Sclerosis in Markazi Province, Iran

BackgroundThe epidemiology of multiple sclerosis (MS) exhibits significant variability all over the world. Additionally, the incidence and prevalence of the disease are geographically diverse in the different provinces of Iran. ObjectivesDue to the lack of a research about the epidemiology of MS in the Markazi province of Iran, the present study aimed to estimate its prevalence and incidence in this province. MethodsThis cross-sectional register study was conducted according to the data related to the MS Society of Markazi province. The inclusion criteria were definite MS during 2010–2019, residence in Markazi province, and membership in the MS society of Markazi province. The annual incidence and prevalence of MS (per 100,000 person-years) were computed by sex and age groups. Further, age-standardized prevalence and incidence rates were calculated based on the Iranian population. A gamma regression model with log link was utilized for comparing the rates over time statistically. The prevalence and incidence rates were computed by using Excel, and R 4.0.5 was applied to fit the gamma model. ResultsIn the study, the total number of MS cases was 1,391, among whom 1,098 (78.9%) and 293 (21.1%) were females and males, respectively. The onset of MS occurred at the mean (S.D) age of 31.76 (8.98) years with a female/male ratio of 3.75. During the study period (2010–2019), the incidence rate of the disease was on the decline, while the prevalence rate elevated, by indicating a rising trend in MS prevalence in both sexes. ConclusionThe results represented the decreasing and increasing trend of the incidence and prevalence of MS in Markazi province over the recent years. The province is one of the regions with a high prevalence and incidence rate of MS compared to the national and global statistical data.

Amyotrophic Lateral Sclerosis and Multiple Sclerosis: More Evidence Suggesting a Link

Objectives Previous reports of the concurrence of multiple sclerosis (MS) and amyotrophic lateral sclerosis (ALS) in the same patients suggest shared pathogenesis, with the C9orf72 mutation as a possible shared genetic link.&#x0D; Methods: Symptoms, neuroimaging, and laboratory data were summarized for patients with ALS and MS within our ALS registry. Using age adjusted MS prevalence rates, we calculated the expected co-occurrence using the binomial test. &#x0D; Results: Clinical and demographic features of the five patients (four female, one male) with ALS and MS are described. Because ALS more frequently occurs in men, observing 4/5 female patients with concurrent ALS/MS showed a borderline expectation difference (P=0.073). The observed co-occurrence of ALS and MS was 5X times higher than the expected frequency of 0.98 (P &lt;0.004). Four patients were found negative for C9orf72.&#x0D; Discussion: Our results suggest a non-random association between MS and ALS, although shared genetic etiology was not found.

NMOSD and MS prevalence in the Indigenous populations of Australia and New Zealand.

We studied the prevalence of neuromyelitis optica spectrum disorder (NMOSD) and multiple sclerosis (MS) in Indigenous populations of Australia and New Zealand with the aim of assessing potential differences. Cases of possible NMOSD and MS were collected from Australia and New Zealand. Clinical details, MR imaging, and serologic results were used to apply 2015 IPND diagnostic criteria for NMOSD and 2010 McDonald criteria for MS. Frequencies of self-determined ethnic ancestry were calculated for confirmed NMOSD, suspected NMOSD, and MS. Prevalence rates for NMOSD and MS according to ancestry were compared. There were 75 cases with NMOSD, 89 with suspected NMSOD, and 101 with MS. NMOSD cases were more likely to have Asian, Indigenous, or Other ancestry compared to suspected NMOSD or MS. There were no differences in the clinical phenotype of NMOSD seen in Indigenous compared to European ancestry populations. Per 100,000, the prevalence estimate for NMOSD in people with Māori ancestry was 1.50 (95% CI 0.52-2.49) which was similar to those with Asian ancestry 1.57 (95% CI 1.15-1.98). NMOSD prevalence in Australian Aboriginal and Torres Strait Islander populations was 0.38 (95% CI 0.00-0.80) per 100,000. The prevalence of NMOSD in the Māori population is similar to South East Asian countries, reflecting their historical origins. The prevalence of MS in this group is intermediate between those with South East Asian and European ancestry living in New Zealand. Both NMOSD and particularly MS appear to be uncommon in the Indigenous populations of Australia.

Temporal trends of incidence and prevalence of multiple sclerosis in Razavi Khorasan Province, Northeast Iran.

The prevalence of multiple sclerosis (MS) in the Persian Gulf countries has been significantly increasing during the past decades. This study was conducted for investigating the prevalence and incidence of MS in Northeast Iran (Khorasan Razavi province). This cross-sectional study was conducted during 1 January 1988 and 23 September 2018. All patients with a clinically definite diagnosis of MS according to the McDonald criteria (2005) and MRI along with the medical diagnosis, recorded in the Khorasan MS society, were considered for calculation of crude and age-standardized prevalence, and incidence rates of MS. The periodic incidence rates were calculated based on the year of onset of MS. Also, we calculated gender ratios for prevalence and incidence rates. The mean age-standardized prevalence and incidence rates of MS in the Khorasan Razavi were 8.69 (95% CI 8.05-9.41) per 100,000 (3.99 (95% CI 3.39-4.74) for males, 13.49 (95% CI 12.37-14.76) for females). Age-standardized prevalence was 48.87 (95% CI 48.37-49.35) per 100,000 (22.47 (95% CI 22.01-22.93) for males, 75.65 (95% CI 74.80-76.51) for females). Also, the mean incidence and prevalence for Mashhad County as capital of province were 11.38 and 59.09 per 100,000 populations, respectively. The female/male ratio was 3.33 for all age groups. Our results showed that this region is a high-risk area for MS like central region of Iran. Our results revealed that the prevalence and incidence of MS in the study area have increased during the recent decades with a sharp slope.

Socioeconomic determinants of global distribution of multiple sclerosis: an ecological investigation based on Global Burden of Disease data

BackgroundSocioeconomic factors may be involved in risk of multiple sclerosis (MS), either indirectly or as confounding factors. In this study two comprehensive indicators reflecting socioeconomic differences, including the Human Development Index (HDI) and Prosperity Index (PI), were used to assess the impact of these factors on the worldwide distribution of MS.MethodsThe data for this global ecological study were obtained from three comprehensive databases including the Global Burden of Disease (as the source of MS indices), United Nations Development Programme (source for HDI) and the Legatum Institute Database for PI. MS indices (including prevalence, incidence, mortality, and disability-adjusted life years) were all analyzed in the form of age- and sex-standardized. Correlation and regression analyses were used to investigate the relationship between HDI and PI and their subsets with MS indices.ResultsAll MS indices were correlated with HDI and PI. It was also found that developed countries had significantly higher prevalence and incidence rates of MS than developing countries. Education and governance from the PI, and gross national income and expected years of schooling from the HDI were more associated with MS. Education was significantly related to MS indices (p < 0.01) in both developed and developing countries.ConclusionIn general, the difference in income and the socioeconomic development globally have created a landscape for MS that should be studied in more detail in future studies.

Prevalence of neuromyelitis optica spectrum disorder in Belo Horizonte, Southeast Brazil

Background: Studies on the prevalence of neuromyelitis optica spectrum disorder (NMOSD) are still scarce. The aim of the current study was to determine the prevalence rate of NMOSD in Belo Horizonte, southeast Brazil, where the prevalence rate of multiple sclerosis (MS) has already been established. Methods: For this observational study, eligible patients had to meet the 2015 International Panel for Neuromyelitis Optica Diagnosis, be seen at the study center between January 2000 and February 2019 and live in Belo Horizonte. The prevalence rate of NMOSD was estimated based on the number of MS and NMOSD patients seen at same Center during the same period, and the previously established prevalence of MS in Belo Horizonte. Results: During the study period, there were 69 patients with NMOSD, 60 (87.0%) of whom were females, and 44 (63.8%) non-whites. The median age at disease onset was 36.7 (4-72) years, the mean EDSS score 4.78±2.36, and the mean ARR 0.57±0.43. Anti-aquaporin-4 immunoglobulin testing was available for 61 (88.4%) patients, of whom 41 (67.2%) had a positive result. During the same period, 280 MS patients were seen. Considering the local known prevalence rate of MS of 18.1/100,000 inhabitants, the estimated NMOSD prevalence rate in Belo Horizonte was 4.52/100,000 (95% CI 3.72-5.43) inhabitants. Conclusion: The prevalence rate of NMOSD in Belo Horizonte is high as compared with those found in most of the studies reported to date.

Prevalence of multiple sclerosis in key cities of Brazil. A study in Joinville, Southern Brazil.

The Brazilian Committee for Treatment and Research in Multiple Sclerosis (BCTRIMS) has launched an initiative to determine the prevalence of multiple sclerosis (MS) in Brazil, based on key cities deemed representative of their regions in terms of demographic and environmental features. To investigate the prevalence rate of MS in Joinville. We reviewed the medical records of all patients who lived in Joinville and met the 2010 McDonald's diagnostic criteria revised for MS on the prevalence day (March 11, 2016). Potential MS patients included individuals treated by all practicing neurologists in the city and the ones found in patients' association and the database of the Municipal Department of Health. Advertisements about the survey were also broadcast on radio and television. Patients who were not living in Joinville on the prevalence day were excluded. All potential MS patients were invited to an in-person diagnostic review, carried out by a panel of experienced neurologists with special expertise in MS on March 11, 2016. The MS prevalence rate was 13.5 per 100,000 inhabitants (95% confidence interval [95%CI] 12.9-14.0/100,000). A total of 51 (66.2%) participants were females, and 26 (33.7%) were males (female to male ratio=1.9:1). Out of the 77 patients, 73 (94.8%) were Caucasians, and four (5.1%) were mixed-race. Despite its latitude location and European colonization, the prevalence rate was below expectation. The intense internal migration from regions with lower MS prevalence rates to Joinville may have played a role in attenuating the increased risk of MS associated with latitude gradient and European ancestry. Prevalence studies in other cities from Southern Brazil with no significant internal migration and taking part in this broad project may clarify this issue.

Epidemiology and comorbidities of adult multiple sclerosis and neuromyelitis optica in Taiwan, 2001–2015

BackgroundThe epidemiology of multiple sclerosis (MS) and neuromyelitis optica (NMO) remains to be clarified or updated in many parts of Asia. This study aims to investigate the epidemiology and comorbidities of MS and NMO during 2001–2015 in Taiwan. MethodsWe conducted a retrospective nationwide population-based study using data from Taiwan's National Health Insurance Research Database. Cases of MS and NMO aged 20 years or above during 2001–2015 were enrolled. The incidence, prevalence, demographic features, and comorbidities were investigated. ResultsWe identified 4627 MS and 861 NMO incident cases aged 20 or above during 2003–2015. The incidence of MS was relatively stationary, while that of NMO apparently rose steeply during the study period. The age-standardized incidence rate of MS and NMO in 2015 were 1.34 and 0.61 per 100,000 person-years, respectively. The age-standardized prevalence rate of MS and NMO in 2015 were 6.69 and 1.47 per 100,000 persons, respectively. The female preponderance was evident for both MS and NMO. Except for diabetes mellitus, the most common autoimmune comorbidities for MS and NMO were Sjogren syndrome and systemic sclerosis, and Sjogren syndrome and systemic lupus erythematosus, respectively. ConclusionsTaiwan has transitioned from low- to medium-risk zone during 2001–2015 in terms of MS prevalence, although its incidence remained stationary. The apparent upsurge of NMO over the period probably reflects increased awareness of this clinical entity. Comorbid autoimmune disorders were relatively common, and overlapping but differential autoimmune comorbidity profiles were noted for MS and NMO.

Patient perspectives on managing uncertainty living with multiple sclerosis

ABSTRACT Introduction: Canada is home to one of the highest global prevalence rates of multiple sclerosis; a disease with causes and treatments that continue to challenge physicians and patients alike. The aim of the present research was to explore patient experiences with the uncertainty that MS introduces to their lives and the role of communication with their physicians for managing uncertainty. Methods: Interviews were conducted with 16 individuals aged 26–75, 5 male and 11 female, living with all three subtypes of multiple sclerosis (February–May 2016). Interview questions related to participant’s experiences at the point of diagnosis and ongoing management, and how and where they find information regarding MS. Data were analyzed using Mishel’s reconceptualized theory of uncertainty in illness to allow us to identify and explain how patients construct mental schema to cope with illness and uncertainty, the significance of uncertainty in their experiences, and how they move through uncertainty to adapt to their prior level of functioning. Results: Data identify heightened uncertainty, and denial, in the initial stages of diagnosis, whereby communication with physicians did little to alleviate feelings of uncertainty. Over time, many participants came to view their physicians as navigators, helping them to manage their own online research and gathering of information beyond traditional health providers (e.g. individuals living with MS). Conclusions: Through the experience of our participants, the present research brings to light the challenges patients face in managing uncertainty and means by which healthcare providers might assist patients in navigating their MS diagnosis.

Air pollution, a possible risk factor for multiple sclerosis.

Studies focusing attention on the effects of environmental pollution on the etiology of multiple sclerosis (MS) are on the increase. The aim of this study was to determine MS prevalence in a city home to an iron and steel factory which causes air pollution. The study was designed as a cross-sectional, population-based, descriptive epidemiologic study. Ereğli city, which has an iron and steel factory and proven air pollution, was screened. Additionally, Devrek city, which is a rural and clean city, located 40km away from Ereğli was assigned and results were compared. A validated questionnaire was used for screening. McDonald 2010 criteria were used to diagnose cases. 32261 people were screened in Ereğli, and 21963 people were screened in Devrek. In total, 41 patients were diagnosed with clinical definite MS. Crude prevalence was found to be 96.1/100000 in Ereğli and 45.5/100000 in Devrek. The mean age of patients was 39.8, and the female/male ratio was 1.9. The results of this study indicate a more than double MS prevalence rate in the area home to an iron and steel factory when compared to the rural city. This supports the hypothesis that air pollution may be a possible etiological factor in MS.

Epidemiological characteristics of multiple sclerosis in Volyn region: a prospective study

Background: Multiple sclerosis (MS) is the most common non-traumatic cause of central nervous system disorders in young people worldwide, leading to cognitive and physical disability. About 20,000 of adult Ukrainians suffer from MS. Prospective studies, taking into account the prevalence and incidence, combined with environmental, territorial and urbanization factors can optimize medical care for patients with MS. A prospective study of MS within Volyn Polissia and Opillya zones has not been conducted before. Objective: To evaluate prospectively the prevalence and morbidity rates of MS among the adult population of Volyn region within the physical-geographical zones. Materials and methods: Epidemiological and medical-statistical methods of morbidity study were used to study features of MS prevalence in the Volyn region. The standard descriptive statistics and factor analysis (principal component method) were used to estimate the variation of a set of indicators. Factor analysis included incidence and prevalence rates of MS in Volyn region since 1999. Results: A statistically significant difference in MS prevalence at the significance level p &lt;0.05 was found in the MS prevalence in 2014 and at the p = 0.005 level in the 2015–2017 section. Also, a statistically significant difference in the incidence of MS at a significance level of p &lt;0.1 was detected in the incidence of MS in 2015 and at the level of p = 0.001 in 2013. Thus, comparing the prevalence and incidence rates, we can conclude that the prevalence of MS in the Volyn Opillya region is significantly higher than in the Volyn Polissia area. Factor analysis (principal component method) was conducted to identify latent factors. As a result, it was found that the 3-factor model allows to describe more than 88% of the variation of the set of indicators: the 1st (main) factor describes 69%, the 2nd - 12,6%, the 3rd - 6,6% (together 88,2%). Conclusions: The prevalence and incidence rates of MS in the Volyn Oblast were found to be uneven. The prevalence of MS in the Volyn Polissia area is lower than in the Volyn Opillia region. The developed 3-factor model allows to describe more than 88% of the variation of the population prevalence of MS. In our opinion, it is advisable to consider the incidence and prevalence rates of MS comprehensively, taking into account environmental, territorial, urban and, not excluded, industrial indicators.

Prevalence and Incidence Rates of Multiple Sclerosis in Lebanon

The prevalence of multiple sclerosis (MS) has been assessed in many countries of the Middle East mostly in Kuwait, Jordan, Saudi Arabia, Oman, Lybia, Tunisia, Iraq and the United Arab Emirates. The prevalence of MS in Lebanon however, is still unknown mainly due to lack of national registries. Based on the Kurtzke classification, Lebanon is located in a low-risk zone for MS. To determine the incidence and prevalence of MS in Lebanon based on a 2018 population census. Lebanese patients diagnosed with MS between January 2018 and December 2018 were identified using the database of the Ministry of Public Health (MOPH), National Social Security Fund (NSSF), Lebanese Army, Cooperative of Government Employees (COOP), Internal Security Forces, and Lebanese General Security based on the reimbursement of disease-modifying therapies (DMTs) by these governmental third-party payers. Nearly all patients with MS in Lebanon receive their therapies through one of these governmental institutions. The crude, age- and sex-specific 2018 prevalence and incidence rates among Lebanese patients were calculated. 2248 MS patients were identified of whom 1454 (67.1%) were females and 712 (32.9%) males (female: male ratio 2:1) with a mean age of 41.8 ± 12.96 years. The 2018 prevalence rate of MS was 62.91 cases per 100,000 persons (95% CI: 60.41 - 65.41). The pediatric prevalence of MS was 2.23 per 100,000 (95% CI: 1.41- 3.05). There was a peak in prevalence rate among patients aged 35-44 years. The overall incidence rate of MS in Lebanon was 8.36 cases per 100,000 (95% CI: 7.45 – 9.27), representing 324 newly diagnosed patients in 2018. The mean age at onset of MS was 34.5 ± 12.5 years. This is the first study to assess the prevalence and incidence rates of MS in Lebanon, confirming that Lebanon is a moderate to high-risk area for MS. Those high rates are commensurate with the recently published studies from the Middle East, pointing to a significant rise in the incidence and prevalence of this disease in our region.

Dramatic changes in multiple sclerosis prevalence in Iran: A descriptive study in ten regions of Iran

Background and Objectives: The prevalence of multiple sclerosis (MS) differs between different regions of Iran. This study aimed to investigate changes in prevalence and incidence rates of MS in ten ethnic and cultural zones of Iran set by the Ministry of Health and Medical Education. Materials and Methods: Information on MS incidence and prevalence was obtained from the national registry of MS during the study period 2006–2013. Demographic data were acquired from the Statistical Centre of Iran. Results: A rising trend of MS prevalence was observed in Iran, and overall, the prevalence of MS increased by 3.67% per year. The highest prevalence rates of MS, and the most dramatic increase in MS prevalence, occurred in the central areas of Iran. However, during the 7-year period, the prevalence gradually increased also in southern and western areas. Conclusion: The prevalence and incidence of MS have been rapidly increasing in all regions of Iran, especially from central to western and southern regions.

The prevalence of multiple sclerosis in the city of Ourense, Galicia, in the north-west of the Iberian Peninsula

Multiple sclerosis is an inflammatory neurodegenerative disease of the central nervous system, which mainly affects young people of working and reproductive age, and represents the first cause of non-traumatic disability in this age group of the population. A north-south latitude gradient is recognised, with prevalence rates increasing as we move away from the equator. This gradient probably represents the genetic predisposition transmitted from the Scandinavian regions through the Viking invasions and could presuppose an influence of the vitamin D deficit related to a lower number of hours of sunshine per year. To determine the prevalence and incidence of multiple sclerosis in the city of Ourense, Galicia. The latitude coordinate of the city of Ourense is 42° 34' N. A retrospective epidemiological study covering the period from 2002 to 2016 was conducted. The prevalence date was 31 December 2016. According to the latest census, the population of the city of Ourense was 105,892 on 1 January 2016. Altogether, 195 cases were recorded, representing a prevalence of 184.1 cases/100,000 inhabitants. In the period 2002-2016, 127 cases of multiple sclerosis were diagnosed, representing an average incidence of 7.86 cases/100,000 inhabitants/year. The city of Ourense has the highest prevalence rate of multiple sclerosis of those studied to date in the Iberian Peninsula, with a figure that brings it closer to the data reported in more northern areas under Nordic and Anglo-American influence.