The prevalence of multiple sclerosis in the city of São Paulo, Brazil, 1997

Misdiagnosis in multiple sclerosis in a Brazilian reference center: Clinical, radiological, laboratory profile and failures in the diagnostic process-Cohort study

BACKGROUND

Multiple sclerosis misdiagnosis remains a problem despite the well-validated McDonald 2017. For proper evaluation of errors in the diagnostic process that lead to misdiagnosis, it is adequate to incorporate patients who are already under regular follow-up at reference centers of demyelinating diseases.

OBJECTIVES

To evaluate multiple sclerosis misdiagnosis in patients who are on follow-up at a reference center of demyelinating diseases in Brazil.

METHODS

We designed an observational study including patients in regular follow-up, who were diagnosed with multiple sclerosis at our specialized outpatient clinic in the Hospital of Clinics in the University of Sao Paulo, from 1996 to 2021, and were reassessed for misdiagnosis in 2022. We evaluated demographic information, clinical profile, and complementary exams and classified participants as "established multiple sclerosis," "non-multiple sclerosis, diagnosed," and "non-multiple sclerosis, undiagnosed." Failures in the diagnostic process were assessed by the modified Diagnostic Error Evaluation and Research tool.

RESULTS

A total of 201 patients were included. After analysis, 191/201 (95.02%) participants were confirmed as "established multiple sclerosis," 5/201 (2.49%) were defined as "non-multiple sclerosis, diagnosed," and 5/201 (2.49%) were defined as "non-multiple sclerosis, undiagnosed."

CONCLUSIONS

Multiple sclerosis misdiagnosis persists in reference centers, emphasizing the need for careful interpretation of clinical findings to prevent errors.

Higher frequency of Human herpesvirus-6 (HHV-6) viral DNA simultaneously with low frequency of Epstein-Barr virus (EBV) viral DNA in a cohort of multiple sclerosis patients from Rio de Janeiro, Brazil

Multiple sclerosis (MS) is a chronic neuroinflammatory and neurodegenerative disease of the central nervous system (CNS). The etiology of MS is not well understood, but it's likely one of the genetic and environmental factors. Approximately 85% of patients have relapsing-remitting MS (RRMS), while 10-15% have primary progressive MS (PPMS). Epstein-Barr virus (EBV) and Human herpesvirus 6 (HHV-6), members of the human Herpesviridae family, are strong candidates for representing the macroenvironmental factors associated with MS) pathogenesis. Antigenic mimicry of EBV involving B-cells has been implicate in MS risk factors and concomitance of EBV and HHV-6 latent infection has been associated to inflammatory MS cascade. To verify the possible role of EBV and HHV-6 as triggering or aggravating factors in RRMS and PPMS, we compare their frequency in blood samples collected from 166 MS patients. The presence of herpes DNA was searched by real-time PCR (qPCR). The frequency of EBV and HHV-6 in MS patients were 1.8% (3/166) and 8.9% (14/166), respectively. Among the positive patients, 100% (3/3) EBV and 85.8% (12/14) HHV-6 are RRMS and 14.4% (2/14) HHV-6 are PPMS. Detection of EBV was 1.2% (2/166) and HHV-6 was 0.6% (1/166) in blood donors. About clinical phenotype of these patients, incomplete multifocal myelitis, and optic neuritis were the main CNS manifestations. These are the first data about concomitant infection of these viruses in MS patients from Brazil. Up to date, our findings confirm a higher prevalence in female with MS and a high frequency of EBV and HHV-6 in RRMS patients.

Estimated prevalence of AQP4 positive neuromyelitis optica spectrum disorder and MOG antibody associated disease in São Paulo, Brazil

BACKGROUND

Numerous studies addressed the prevalence of multiple sclerosis, but prevalence studies of NMOSD and, particularly, MOGAD are scarce. We aimed to estimate the prevalence of NMOSD and MOGAD in the city of São Paulo, based on the known prevalence of MS.

METHODS

In this observational study, we determined the total number of patients with central nervous system demyelinating disease on regular follow-up in a university referral center in São Paulo, from May 2019 to May 2021 according to the diagnosis of multiple sclerosis (MS), NMOSD and MOGAD using the current diagnostic criteria for these diseases. We used the MS: NMOSD and MS: MOGAD ratios to estimate the ratio of these diseases in São Paulo, Brazil.

RESULTS

We identified 968 patients with MS, 133 patients with AQP4 positive NMOSD, and 28 patients with MOGAD. We found the MS: NMOSD ratio of 7,28 and the MS: MOGAD ratio of 34,57. We estimated a prevalence of 2,1 per 100,000 inhabitants for NMOSD and of 0,4 per 100,000 inhabitants for MOGAD.

CONCLUSION

The prevalence of NMOSD is high in São Paulo, but the prevalence of MOGAD is low when compared with the prevalence found in most of the studies reported to date.

Systematic literature review and meta-analysis of the prevalence of secondary progressive multiple sclerosis in the USA, Europe, Canada, Australia, and Brazil

Background

Secondary progressive multiple sclerosis (SPMS) is a subtype of multiple sclerosis (MS), which is a chronic neurological disease, characterised by inflammation of the central nervous system. Most of MS patients eventually progress to SPMS. This study estimates the prevalence of SPMS in the United States of America, Europe, Canada, Australia, and Brazil.

Methods

A systematic literature search of the Medline and Embase databases was performed using the OVID™ SP platform to identify MS epidemiological studies published in English from database inception to September 22, 2020. Studies reporting the prevalence of MS and proportion of SPMS patients in the included population were selected. The pooled prevalence of SPMS was calculated based on the proportion of SPMS patients. The Loney quality assessment checklist was used for quality grading. A meta-analysis of the proportions was conducted in RStudio.

Results

A total of 4754 articles were retrieved, and prevalence was calculated from 97 relevant studies. Overall, 86 medium- and high-quality studies were included in the meta-analysis. Most studies were conducted in European countries (84 studies). The estimated pooled prevalence of SPMS was 22.42 (99% confidence interval: 18.30, 26.95)/100,000. The prevalence of SPMS was more in the North European countries, highest in Sweden and lowest in Brazil. A decline in SPMS prevalence was observed since the availability of oral disease-modifying therapies. We also observed a regional variation of higher SPMS prevalence in urban areas compared with rural areas.

Conclusion

High variability was observed in the estimated SPMS prevalence, and the quality of the studies conducted. The influence of latitude and other factors known to affect overall MS prevalence did not fully explain the wide range of inter-country and intra-country variability identified in the results.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-022-02820-0.

Human endogenous retrovirus and multiple sclerosis: A review and transcriptome findings

Multiple Sclerosis is an autoimmune disease with an unknown etiology. Both genetic and environmental factors are believed to trigger MS autoimmunity. Among the environmental factors, infectious agents have been extensively investigated, and the Human Endogenous Retroviruses (HERVs), especially HERV-W, are believed to be associated with MS pathogenesis. HERVs are derived from ancestral infections and comprise around 8% of the human genome. Although most HERVs are silenced, retroviral genes may be expressed with virion formation. There is extensive evidence of the relationship between HERV-W and MS, including higher levels of HERV-W expression in MS patients, HERV-W protein detection in MS plaques, and the HERV-W env protein inducing an inflammatory response in in vitro and in vivo models. Here we discuss possible links of HERVs and the pathogenesis of MS and present new data regarding the diversity of HERVs expression in samples derived from MS patients.

Multiple sclerosis in Peru: National prevalence study using capture-recapture analysis

BACKGROUND

There is scarce epidemiological data on Multiple Sclerosis (MS) in Latin America. National epidemiological studies are needed to guide the health policy related to MS.

OBJECTIVE

To determine MS national prevalence in Peru and describe clinical and epidemiological characteristics of the disease.

METHODS

We conducted a cross-sectional prevalence study in Peru's four largest regions using two sources. We included adult patients diagnosed with MS by a neurologist using the McDonald criteria. We performed a capture-recapture analysis using the nearly unbiased estimator model, and calculated prevalence as the proportion of the adult Peruvian population in 2016. Additionally, we summarized patients epidemiological and clinical characteristics.

RESULTS

We identified 417 cases: 135 from the first source and 282 from the one. We found a point prevalence of 9.12 cases per 100 000 inhabitants (95% CI: 5.6 - 12.6). The age range was 35 to 45 years-old, and 51.9% were female. The most common type of MS was relapsing-remitting (79.3%) and the most frequent treatment was subcutaneous IFN-1b (40.7%).

CONCLUSION

Peru has a medium MS prevalence compared to other Latin American countries. Lima is the region with the highest number of cases, with similar clinical characteristics to other countries in the region.

Secondary progressive multiple sclerosis: a systematic review of costs and health state utilities

Objective: To identify evidence in the literature presenting the economic and humanistic (based on health state utility values [HSUVs]) burden of multiple sclerosis (MS) and report the incremental burden of secondary progressive MS (SPMS) compared with relapsing-remitting MS (RRMS).Methods: Electronic databases (Embase, MEDLINE, MEDLINE In-Process, Cochrane Library) and other relevant repositories were systematically searched from the date of inception until November 2019 for evidence on the economic burden of MS, or HSUVs in patients with MS. Data were extracted from studies investigating cost data or HSUVs for patients with SPMS compared with RRMS.Results: In total, 25 studies were identified that reported data on the economic and HSUV burden of SPMS versus RRMS: 18 studies reported cost data and nine presented HSUVs. Overall, costs associated with SPMS were consistently higher than those for RRMS. Major cost drivers appeared to shift following transition from RRMS to SPMS, with higher direct medical costs associated with RRMS than with SPMS, while the opposite was true for direct non-medical costs and indirect costs. In all studies presenting HSUVs specifically in patients with SPMS, the disease burden was greater (indicated by lower HSUV scores or a negative regression coefficient vs RRMS) for patients with SPMS than for those with RRMS. Fatigue and psychological stress (including depression) were identified as key drivers of this reduced health-related quality of life (HRQoL).Conclusions: Our findings indicate that SPMS is associated with higher costs and more substantial HRQoL decrements than RRMS. These results highlight the substantial unmet need for effective treatments that can slow disease progression in patients with SPMS, which, in turn, would reduce the rate of HRQoL deterioration and increasing healthcare costs.

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

BACKGROUND

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.

OBJECTIVE

To investigate the prevalence rate of MS in Joinville.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Prevalence of multiple sclerosis in Goiânia, Goiás, Brazil

OBJECTIVE

Multiple sclerosis (MS) prevalence, in some cities in Brazil, was estimated and was found to range from 0.75 to 30.7/100,000. The reasons for such a large variation in rates of prevalence are not clear, but environment and genetics help to explain this phenomenon.

METHODS

A cross-sectional study using three sources of case ascertainment to estimate the prevalence of MS in the city of Goiânia in December, 2015.

RESULTS

A total of 318 MS patients was found after removing overlapping sources. The prevalence of MS was 22.4/100,000 population.

CONCLUSION

Our study was the first in Goiás and the third in the midwest region, and we found a great increase in the prevalence of MS in the region. It is necessary to perform other studies using the same methodology for a more accurate evaluation of the true prevalence of MS in Brazil.

Increasing Incidence and Prevalence of Multiple Sclerosis in Puerto Rico (2013-2016)

BACKGROUND

The incidence of multiple sclerosis (MS) has been increasing worldwide over the past decades. However, this upward trend has not been examined at the country level in Latin America and the Caribbean (LAC). The aims of this study are to examine trends of MS incidence over 4 years and to provide age- and gender-standardized incidence rate estimates for a Caribbean island.

METHODS

Data from the Puerto Rico (PR) MS Foundation's registry was used to identify all newly diagnosed MS cases between 2013 and 2016. MS patients were 18 years and older and met the 2010 revised McDonald criteria. Age- and gender-standardized incidence rates were estimated.

RESULTS

A total of 583 new MS cases were diagnosed in PR from 2013 to 2016. The age- and gender-standardized MS incidence rate for PR increased from 6.1/100,000 in 2013 to 6.7/100,000 in 2016. The annual age-standardized MS incidence rates for females rose from 8.4/100,000 in 2013 to 9.8/100,000 in 2016 and were higher than males, which remained around 3.7/100,000.

CONCLUSION

Incidence estimates for PR were higher than other LAC countries but consistent with MS increases in other world regions. Our findings tend to rule out several prior potential environmental explanations for high MS incidence rates.

Time-trend analysis and developing a forecasting model for the prevalence of multiple sclerosis in Kohgiluyeh and Boyer-Ahmad Province, southwest of Iran

OBJECTIVE

This study was designed and implemented to assess the current situation and to estimate the time trend of multiple sclerosis (MS), as well as to explain potential factors associated with such a trend.

METHODS

This longitudinal study was carried out based on analysis of the data from the monitoring and treatment surveillance system for 421 patients with MS in Kohgiluyeh and Boyer-Ahmad Province, Iran, from 1990 to 2015. To this end, curve estimation approach was used to investigate the changes in prevalence and incidence of the disease, and univariate time series model analysis was applied in order to estimate the disease incidence in the next 10 years.

RESULTS

The mean and standard deviation of age were 29.78 and 8.5 years at the time of diagnosis, and the mean and 95% confidence interval of age were 29.18 (28.86-30.77) and 29.68 (28.06-31.30) at the time of diagnosis for women and men, respectively. The sex ratio (males to females) was estimated as 3.3, and the prevalence of the disease was estimated as 60.14 in 100,000 people. The diagram of the 35-year trend of the disease indicated three distinct patterns with a tendency to increase in recent years.

CONCLUSION

The prevalence and incidence trend of the disease in the study population is consistent with regional and global changes. Climatic and environmental factors such as extreme weather changes, dust particles, expansion of the application of new industrial materials, and regional wars with potential use of banned weapons are among the issues that may, in part, be able to justify the global and regional changes of the disease. Predictive models indicate a growing trend of the disease, highlighting the need for more regular monitoring of the disease trend in upcoming years.

Multiple sclerosis epidemiology in Latin America: An updated survey

Novel epidemiological data have appeared in recent years in Latin America (LATAM). The objective of this study was to perform an updated systematic review of the epidemiology of the disease reported in LATAM.

DNA damage and postural balance in multiple sclerosis patients

Abstract Introduction: Multiple Sclerosis (MS) is a chronic inflammatory disease characterized by infiltration of inflammatory cells on the Central Nervous System (CNS). There is evidence that cumulative DNA damage can contribute to various mechanisms underlying MS lesions. Changes in postural balance are frequent observations in subjects with MS. Objective: Evaluated the DNA damage index (DDI)) and postural balance in patients with MS. Methods: A case-control study was conducted with 28 subjects matched for sex, age, and body mass index, divided into MS group and control. The DDI was assessed by comet assay and postural balance through recording the body oscillations of the center of pressure (COP), in the anterior-posterior and lateral middle directions. Results: Showed higher DDI in MS patients (21.3 ± 4.8) than controls (7.9 ± 6.1). Significant differences between groups were also noted in postural control parameters. The wider ranges of postural sway were observed in the MS group. The associations between DDI and postural control parameters showed weak, but significant correlations. No associations were found between DDI and time of diagnosis of MS. Conclusion: People with MS had higher DDI and larger body oscillations than healthy individuals.

Disability and progression in Afro-descendant patients with multiple sclerosis

ABSTRACT Multiple sclerosis (MS) prevalence is higher in Caucasian (CA) populations, narrowing the analysis of the impact of Afro-descendant (AD) populations in disease outcomes. Even so, recent studies observed that AD patients have a more severe course. The main objective of this study is to confirm and discuss, through a systematic review, that being AD is a risk factor for disability accumulation and/or severe progression in patients with MS. A systematic review of published data in the last eleven years was performed, which evaluated clinical aspects and long term disability in patients with MS. Fourteen studies were included. Of these fourteen articles, thirteen observed a relationship between ancestry and poorer outcome of MS. African ancestry is a condition inherent in the patient and should be considered as an initial clinical characteristic affecting prognosis, and influencing which therapeutic decision to make in initial phases.

Epidemiology of Multiple Sclerosis

The epidemiology of multiple sclerosis (MS) includes a consideration of genetic and environmental factors. Comparative studies of different populations have revealed prevalence and incidence rates that vary with geography and ethnicity. With a prevalence ranging from 2 per 100,000 in Japan to greater than 100 per 100,000 in Northern Europe and North America, the burden of MS is similarly unevenly influenced by longevity and comorbid disorders. Well-powered genome-wide association studies have investigated the genetic substrate of MS, providing insight into autoimmune mechanisms involved in the etiopathogenesis of MS and elucidating possible avenues of biological treatment.

Increasing incidence of multiple sclerosis among women in Buenos Aires: a 22 year health maintenance organization based study

Studies in multiple sclerosis (MS) suggest a trend of increasing disease prevalence and incidence, and especially, a disproportional increase in the incidence of multiple sclerosis in women. The objective of this study was to evaluate the incidence of MS over 22 years and to determine the ratio in incidence of men to women in a health maintenance organization from Buenos Aires, Argentina. The population was made up of all members of a hospital-based HMO affiliated between January 1992 and December 2013. Each person was followed contributing time at risk. Cases with definite diagnosis of MS were included. Incidence density was calculated with 95 % confidence intervals and compared between women and men. 165,456 subjects were followed for a total of 1,488,575 person-years, of whom 42 developed MS. Incidence density was 3/100,000 person-years (95 % CI 2.1-3.5/100,000 person-years). During this period (1992-2013), the incidence rate in women increased from 1/100,000 (95 % CI 0.8-1.6) to 4.9/100,000 (95 % CI 4.1-5.4) (p < 0.001), while in men the incidence ranged from 1.4/100,000 (95 % CI 1-1.7) to 1.8 (1.3-2.1) (p = 0.16). Incidence density during the study period increased significantly in women but not in men. This is the first report of this phenomenon in Latin America region.

Clinical and epidemiological profile of patients diagnosed with multiple sclerosis in João Pessoa, Paraíba, Brazil

Prevalence rates of multiple sclerosis (MS) suggest an interrelationship between genetic and environmental factors, ranging worldwide.Objectives Clinical and epidemiological characterization of MS patients in João Pessoa, Paraíba city.Methods Study involving patients treated in five services in the city.Results It included 87 patients with MS, representing a prevalence of 12.0 cases/100,000 population, mainly women (77%) and white people (66.7%) with mean age of 43 years and average age of the first outbreak of 32.2 years. Motor symptoms (65.5%) and relapsing-remitting clinical form (78.2%) predominated; the average of the Expanded Disability Status Scale (EDSS) scores was 3.5 and 72% used a type of immunomodulatory drug. There was a positive correlation between the number of outbreaks and the duration of the disease with EDSS scores.Conclusions The prevalence of the disease is considered average. The clinical and epidemiological characteristics are in line with most similar Brazilian studies.

Relato de Experiência em Acompanhamento Cognitivo com um Paciente com Esclerose Múltipla

A Esclerose Múltipla (EM) é uma doença crônica e autoimune, caracterizada por desmielinização, inflamação e neurodegeneração do Sistema Nervoso Central. Entre 30 e 50% dos indivíduos com EM apresentam comprometimento cognitivo. O processo de reabilitação cognitiva visa capacitar o paciente a conviver, reduzir e/ou superar os déficits cognitivos decorrentes da doença. Este trabalho relata a experiência de uma estagiária de Psicologia ao participar de um projeto de extensão universitária de acompanhamento cognitivo a um paciente com EM. Inicialmente o paciente foi submetido à avaliação neuropsicológica, identificando funções cognitivas preservadas e déficits. Foram observados déficits na recordação tardia, compreensão léxica, compreensão aritmética e aprendizagem numérica. Posteriormente, o paciente recebeu acompanhamento cognitivo semanal pelo período de seis meses. Após o período do acompanhamento, foi feita a reavaliação neuropsicológica. Observou-se melhora significativa na capacidade de recordação tardia e na aprendizagem aritmética, que deixaram de consistir em déficits. Além disso, houve abrandamento do déficit na compreensão aritmética. Os demais resultados permaneceram sem alterações. O trabalho mostra o impacto positivo que o acompanhamento cognitivo pode trazer ao paciente com EM e como a experiência de extensão pode auxiliar na formação dos estudantes de Psicologia.

Differences in utility scores obtained through Brazilian and UK value sets: a cross-sectional study

Background

Multiple sclerosis (MS) is a chronic disease associated with several impacts; especially regarding patients’ health-related quality of life (HRQL). EuroQol 5 Dimensions questionnaire (EQ-5D) provides self-reported analysis of HRQL and utility scores. Although the British algorithm to convert EQ-5D responses into utility is the most used in the literature, national settings is more appropriate for health policy decision makers. A Brazilian algorithm is available, but not used in MS patients yet. Primarily, this study aimed to address potential differences in utility scores obtained through Brazilian and British value sets. Secondary objective was to determine the role of disability, fatigue and patients socio-demographic and clinical characteristics relevant to MS on the utility scores reported by Brazilian patients.

Methods

Cross-sectional study with MS patients treated in 8 Brazilian sites. Patients were interviewed about socio-demographic and clinical characteristics, self-reported disability level, HRQL and impact of fatigue on daily living. Disability level, HRQL and impact of fatigue were assessed using the Expanded Disability Status Scale (EDSS) and the Brazilian versions of EQ-5D-3L and Modified Fatigue Impact Scale (MFIS-BR), respectively. Patients were classified in subgroups according to EDSS (mild: 0–3; moderate: 4–6.5; severe: >7) and the self-perceived impact of fatigue (absent: ≤38 points; low: 39–58; high: ≥59). EQ-5D-3 L data was converted into a utility index using an algorithm developed by a Brazilian research group (QALY Brazil) and also the UK algorithm. Differences between utility scores were analysed through Wilcoxon test.

Results

Two hundred and ten patients were included in the study. Utility index mean scores of 0.59 (SD = 0.22) and 0.56 (SD = 0.32) for the Brazilian and UK algorithms were observed, respectively, without statistically significant difference for the distribution of data (p = 0.586). However, when utility scores were lower than 0.5, Brazilian algorithm provided higher estimates than UK with a better agreement between the scores found closer to 1. The same trend was observed when data was stratified for EDSS and impact of fatigue, with statistically significant difference between scores in categories of mild/severe disabilities and absent/high impact of fatigue.

Conclusions

Results suggest that Brazilian value set provided higher utility scores than the UK, particularly for measures below 0.5.

The profile of patients followed at the Neuroimmunology Clinic at UNIFESP: 20 years analysis

Objective To describe the clinical activities at the Neuroimmunology Clinic of the Universidade Federal de São Paulo (UNIFESP) from 1994 to 2013. Method The final diagnosis of all patients that attended the center was reviewed and established upon specific guidelines for each disease. The number of total appointments and extra clinical activities (reports and prescriptions) were also analyzed, as are part of routine activities. Results 1,599 patients attended the Clinic from 1994 to 2013: 816 with multiple sclerosis (MS), 172 with clinical isolated syndromes, 178 with neuromyelitis optica (NMO), 216 with other demyelinating disease, 20 with metabolic disorder, 42 with a vascular disease and 155 with other or undetermined diagnosis. A mean 219 outpatient visits and 65 extra clinical activities were performed monthly. Conclusion We identified that 15% of patients seen have NMO. As patients with NMO have a more severe disease than MS, this data may be important for planning local health care policies.

Is it time for a new global classification of multiple sclerosis?

BACKGROUND

The geographic distribution of multiple sclerosis (MS) is classically divided into three zones based on frequency that were established by Kurtzke in the early 1970s. In recent years, an increasing number of epidemiological studies have shown significantly higher MS prevalence and incidence rates.

OBJECTIVE

The aim of this study was to review and update the geographic distribution of MS using incidence, prevalence and disease duration from the latest epidemiology surveys.

METHODS

We conducted a systematic review of articles on MS epidemiology published between January 1, 1990 and December 31, 2012.

RESULTS

MS studies were grouped by continent: the Americas, Europe, Asia, Australia/New Zealand, and Africa. A total of 101 studies were identified according to the inclusion criteria, and 58 reported incidence estimates. Globally, the median estimated incidence of MS was 5.2 (range: 0.5-20.6) per 100,000 p-yrs, the median estimated prevalence of MS was 112.0 (with a range of 5.2-335) per 100,000 p-yrs, and the average disease duration was 20.2 years (range: 7.6-36.2).

CONCLUSION

In the past few decades, the global prevalence and incidence patterns of MS have changed dramatically. Regardless of the reason of increasing prevalence and incidence rate, we suggest the need for a novel classification system based on global MS disease burden. Adopting such a system would improve economic efficiency and prioritization in health policy planning for MS.

[Nursing care systematization for outpatient treatment care of patients with multiple sclerosis]

An experience report of nurses in the implementation of care systematization in ambulatory care in an interdisciplinary care center for patients with multiple sclerosis of a public hospital in Fortaleza, Ceará, Brazil. This implementation is based on the NANDA International, Inc., Nursing Interventions Classification, and Nursing Outcomes Classifications. One of the results concerns systemized nursing care, which has enabled the identification and understanding of the responses of MS patients to potential and current health problems. Systematization entails expanding knowledge through a practice based on approach and encourage further research scientific evidence, in addition to promoting the role of the nurse in acomprehensive approachand encourage further research.

The prevalence of multiple sclerosis in Santa Maria, Rio Grande do Sul, Brazil

Multiple sclerosis (MS) is one of the leading causes of neurologic deficits in young adults and can lead to physical, intellectual and emotional problems. Approved treatments are expensive and are among the 10 highest budgets of the Brazilian Health Ministry. Given the diverse prevalence of MS among Brazilian regions, it is important to determine prevalence rates across the country. Seven studies have assessed MS in Brazil and reported rates ranging from 15 cases to 18 cases per 100,000 inhabitants. It has been hypothesized that this rate is even higher in southern Brazil, which has a high proportion of European heritage (mostly German and Italian) immigrants. Here, we report that the prevalence of MS in the city of Santa Maria, Rio Grande do Sul, Brazil, is 27.2 cases/100,000 inhabitants.

Urinary dysfunction in women with multiple sclerosis: analysis of 61 patients from rio de janeiro, Brazil

The aim of the present study is to describe the type and frequency of bladder dysfunction in a series of female patients with multiple sclerosis (MS) from Rio de Janeiro, and analyze the role of the urologist in the multidisciplinary team. A team of urologists and a neurologist from the Hospital da Lagoa, Rio de Janeiro, Brazil, interviewed female patients with MS about illness onset, urologic follow-up since diagnosis, current stage of the disease and current urological symptoms. The interview was followed by an urodynamic testing, ultrasound of the urinary tract and urinalysis. Data resulting from the interviews and exam results were gathered and submitted to statistical evaluation. Sixty one patients were evaluated, with average age of 41.4 years. Urinary symptoms such as urinary incontinence, urinary hesitancy, urinary retention, urinary urgency and incomplete bladder emptying were reported in 44% of patients as initial signs of MS disease. Mean disease duration was 8 years and all patients (100%) with the primary progressive form of the disease and 63.5% with the relapsingremitting presentation had urological symptoms. Analysis of complementary exams showed that 37.7% of urinalysis, 8.2% of the urinary tract ultrasound exams and 66.7% of the urodynamic evaluations were abnormal and the most frequent abnormality were overactive neurogenic bladder. Only 4 patients (6.6%) had seen an urologist during the course of their disease and only 1.6% had performed an urodynamic evaluation. This study shows a high prevalence (68%) of urinary dysfunction in a female population with MS. Urologic care should be part of the multidisciplinary team since the beginning of the disease. An urodynamic evaluation and simple urinalysis should be included in the routine testing during disease follow-up due to the high incidence of neurogenic bladder and other urologic complications.

There is much to be learnt about the costs of multiple sclerosis in Latin America

METHOD: A systematic review of the literature from 1990 to 2011 was conducted. Outcome measures included: mean cost of disease modifying therapies (DMTs), mean cost of treatment of relapses and mean cost of disease by stage stratification measured by the expanded disability status scale (EDSS). RESULTS: Seven studies from three countries (Brazil, Argentina and Colombia) were included. In 2004, in Argentina, the mean cost of DMT treatment was reported to be USD 35,000 per patient treated. In Brazil, the total MS expenditure of DMTs rose from USD 14,011,700 in 2006 to USD 122,575,000 in 2009. Patient costs ranged between USD 10,543 (EDSS 8-9.5) and USD 25,713 (EDSS 3-5.5). Indirect costs markedly increased for the EDSS 8-9.5 patients. CONCLUSION: Further research assessing the economic burden of MS in LA is warranted.

Incidence and prevalence of multiple sclerosis in the Americas: a systematic review

BACKGROUND

The incidence and prevalence of multiple sclerosis (MS) varies considerably around the world. No previous study has performed a comprehensive review examining the incidence and prevalence of MS across the Americas. The purpose of this study was to systematically review and assess the quality of studies estimating the incidence and/or prevalence of MS in North, Central and South American regions.

METHODS

A comprehensive literature search was performed using MEDLINE and EMBASE from January 1985 to January 2011. Search terms included 'multiple sclerosis', 'incidence', 'prevalence' and 'epidemiology'. Only full-text articles published in English or French were included. Study quality was assessed using an assessment tool based on recognized guidelines and designed specifically for this study.

RESULTS

A total of 3,925 studies were initially identified, with 31 meeting the inclusion criteria. The majority of studies examined North American regions (n = 25). Heterogeneity was high among all studies, even when stratified by country. Only half of the studies reported standardized rates, making comparisons difficult. Quality scores ranged from 3/8 to 8/8.

CONCLUSION

This review highlights the gaps that still exist in the epidemiological knowledge of MS in the Americas, and the inconsistencies in methodologies and quality among the published studies. There is a need for future studies of MS prevalence and incidence to include uniform case definitions, employ comparable methods of ascertainment, report standardized results, and be performed on a national level. Other factors such as sex distribution, ethnic make-up and population lifestyle habits should also be considered.

The epidemiology of multiple sclerosis in Latin America and the Caribbean: a systematic review

The incidence and prevalence of multiple sclerosis (MS) varies geographically as shown through extensive epidemiological studies performed mainly in developed countries. Nonetheless, scant data is available in Latin America and the Caribbean (LAC). The objective of this review is to assess epidemiological data of MS in LAC. We conducted a systematic review of published articles and gray literature from January 1995 to May 2011. Twenty-two studies met the inclusion criteria after full-text review. Incidence data were found in only three studies and ranged from 0.3 to 1.9 annual cases per 100,000 person-years. Prevalence was reported in 10 studies and ranged from 0.83 to 21.5 cases per 100,000 inhabitants. The most prevalent subtype of MS was the relapsing–remitting form (48% to 91% of the series). No data about mortality were found. This study showed low frequency for MS in LAC compared with North American and European countries. The role of environmental and genetic factors should be well studied, providing new insights about its etiology.

The prevalence of multiple sclerosis in Belo Horizonte, Brazil

Investigations on the prevalence rates of multiple sclerosis (MS) around the world have yielded important clues on the interplay between genetic susceptibility and environmental factors. As Brazil is a huge country laid on many latitudes and inhabited by population with distinct ethnic backgrounds, it might be assumed that the frequency of MS varies in its different regions. Objective: To determine the prevalence rate of MS in Belo Horizonte, the capital of the State of Minas Gerais, Southeastern Brazil. Methods: We used six sources to draw up a provisional list of identified cases of MS. Only patients with diagnosis of clinically definite MS according to Poser Committee criteria were included. Results: The calculated crude MS prevalence was 18.1/100,000 inhabitants. Conclusions: The MS prevalence in Belo Horizonte is similar to that found in São Paulo and Botucatu, two other cities in southeastern Brazil with similar ethnic background.

Incidence of multiple sclerosis in Chile. A hospital registry study

OBJECTIVE

To study the incidence of MS in Chile by examining the hospitalizations across all geographical regions of the country and to examine whether there is a correlation between these rates and the latitude or ultraviolet radiation.

METHODS

This is a descriptive study examining the national registry of hospitalizations because of MS (code G35 in ICD-10) from January 1, 2001, to December 31, 2006. Incidence rates were calculated by gender and geographical region and standardized to the world population estimated for 2010.

RESULTS

A total of 6857 hospitalizations were analyzed. There were 935 individuals; 63.9% were women. The mean incidence rate for 2002-2006 period was 0,90 (95% CI: 0.75-1.05). The annualized incidence rates for regions from North to South were as follows: I Tarapaca 0.54 (95% CI: 0.0-1.21), II Antofagasta 0,93 (0.10-1.75), III Atacama 1.07 (0.0-2.31), IV Coquimbo 0.63 (0.01-1.24), V Valparaiso 0.83 (0.38-1.27), VI O'Higgins 0.72 (0.14-1.30), VII Maule 0.52 (0.06-0.98), VIII BIO BIO 0.81 (0.41-1.21), IX Araucanía 0.43 (0.0-0.86), X Los Lagos 0.91 (0.35-1.46), XI Aysen 0.99 (0.0-2.98), XII Magallanes 3.54 (0.57-6.51), and XIII Metropolitana 1.10 (0.84-1.36). There were no significant correlations between hospitalization rates and latitude, except for region XII. UV radiation levels showed significant differences only for region XII.

CONCLUSION

There is a moderate risk of MS in Chile. The southernmost region showed significantly higher incidence rates than those in the rest of the country (a cluster zone). We did not find any correlation between incidence rates and latitude or UV radiation.

Multiple sclerosis in Caucasians and Latino Americans

Epidemiological and genetic studies suggest that the prevalence, median age of onset, and specific phenotypes of multiple sclerosis (MS) are different in Caucasians and Latino Americans. Recent epidemiological studies indicate an increase in MS prevalence in Latin America (LA), where the south-north gradient of latitude described for Nordic countries does not exist. Analysis of MS epidemiological and specific aspects in LA suggests that susceptibility and clinical behavior of the disease are related to mixtures and admixtures of genes in the population. MS is not present in Amerindians with Mongoloid genes, such as occurs in other pure ethnic groups. Surely, future studies will be carried out to obtain more reliable information. In this review, we contrast and analyze the available data of MS in LA and endemic countries.

Latitudinal prevalence gradient of multiple sclerosis in Latin America

BACKGROUND

Multiple sclerosis (MS) has a unique geographical distribution that reflects both genetic and environmental factors. Many studies have shown a positive correlation between MS frequency and latitude across both large and small geographical regions. However, scarce data have been published on the epidemiology of MS in Latin America and no study has evaluated latitudinal variation.

OBJECTIVE

To evaluate the effect of latitude on MS prevalence in Latin America.

METHODS

We conducted a systematic review of MS prevalence during January 2011. Prevalence rates were collected from eligible publications. The effect of latitude on prevalence was analyzed using linear regression.

RESULTS

A total of ten studies were eligible for analysis, corresponding to six countries, spanning from Panama to Argentina. The crude prevalence of MS ranged from 0.75 to 21.5 per 100,000. We found a strong and significant association between prevalence and latitude (r(2) 0.8; p < 0.001) and determined an increase in prevalence of 0.33 per 100,000 per degree latitude.

CONCLUSION

Our findings suggest a latitudinal prevalence gradient of MS in Latin American countries between Panama and Argentina.

Multiple sclerosis in Hispanics: a study of clinical disease expression

Background: Hispanics living with multiple sclerosis (MS) in the United States are not well defined.

Objective: To describe the clinical characteristics of MS among Hispanic Whites (HW) in Southern California with those of non-Hispanic Whites (NHW).

Methods: We performed a medical chart review to identify all cases of HW with MS ( n = 125) who were treated at our institution during a 1-year period. We also identified cases of NHW with MS (100 NHW) treated at those clinics. All HW patients were interviewed to ascertain ancestry including detailed migration history. Disease progression was assessed by ambulatory disability and defined as Expanded Disability Status Scale (EDSS) score ≥6.

Results: Compared with NHW, HW were more likely to have a relapsing–remitting form of MS and a younger age of onset (28.4 ± 0.97 years) with presenting symptoms of optic neuritis and transverse myelitis. However, overall ambulatory disability did not differ between HW and NHW. Migration to the US at age >15 years was associated with increased risk of disability in HW.

Conclusions: HW living in the USA may be at risk of developing MS at an earlier age compared with NHW. Migration history can play an important role in the management of HW with MS.

Clinical and epidemiological profile of patients with multiple sclerosis in Uberaba, Minas Gerais, Brazil

Multiple sclerosis (MS) is an immune-mediated disease that affects the central nervous system. Clinical presentation and prevalence vary widely around the world. OBJECTIVE: To describe the clinical and epidemiological aspects of patients with MS in Uberaba (MG). METHOD: We conducted a transversal descriptive study, with data analysis of 35 patients with MS. RESULTS: Prevalence of MS was 12.5 cases/100,000 inhabitants, with a predominance in females (71.4%) and Caucasoid (85.7%). The current average age was (43.8 ys). The most common initial symptom was sensory (40%), followed by optical neuritis (25.7%). Expanded Disability Status Scale average score was 2.4. The relapsing-remitting form was predominant (88.6%), most (74.3%) were on immunomodulatory treatment and (40%) had college education. CONCLUSION: Prevalence of MS in Uberaba (MG) is considered average in accordance to Kurtzke and Page and clinical features are consistent with most Brazilian studies.

Gender issues in multiple sclerosis: an update

Although multiple sclerosis (MS) affects both women and men, women are more susceptible to MS than men. Accumulating evidence indicates that the incidence and prevalence of MS is increasing, more so in women than in men. Owing to pregnancy, differing hormonal states and distinct social roles, the impact of MS differs between women and men. Since Patricia K Coyle published a review on gender issues in MS, multiple studies have added to the body of knowledge. This update will summarize the current thinking on gender-related issues in MS and we will address incidence and prevalence, hormonal factors, pregnancy and breastfeeding, genetics, course and prognosis, imaging, treatment and psychosocial aspects. Future progression within this field will help elucidate the cause of and define the treatment of MS.

A quantitative analysis of suspected environmental causes of MS

BACKGROUND

Multiple sclerosis (MS) is a disease with purported environmental causes. Consistent correlations have been found in various settings for latitude, smoking exposure, sunlight, and vitamin D deficiency. We analysed the contribution of various environmental factors to the risk of developing MS from a population perspective.

METHODS

We collated global data of MS prevalence from 54 studies over the previous ten years and calculated the degree of risk contributed by latitude, longitude, ultraviolet radiation (from NASA satellite data and formulae for available sunlight hours), population smoking rates (from WHO data), gender, study date, study demographics, and several socioeconomic factors. We report a very significant negative correlation between MS prevalence and available ultraviolet (UV) radiation.

RESULTS

The lack of available UV radiation outweighs other factors by at least 20 fold (p < 10⁻⁸) from single variate regression analysis. Multiple regression analysis revealed that latitude and longitude are also significant factors; smoking may also provide a very minimal role. The eight prevalence studies from Scandinavia produced prevalences that were lower than expected, given their global geospatial positioning.

CONCLUSIONS

The available ultraviolet radiation is a significant environmental factor, more so than all the other factors examined.

Ophthalmologic manifestations commonly misdiagnosed as demyelinating events in multiple sclerosis patients

PURPOSE OF REVIEW

Multiple sclerosis may affect both afferent and efferent visual pathways, and sometimes physicians err on ordinary ophthalmologic diagnosis due to overlapping symptoms between demyelinating and nondemyelinating visual diseases. The present article highlights nondemyelinating ocular occurrences due to physiologic or other pathologic processes that may appear in some patients.

RECENT FINDINGS

Optic neuritis is representative of the most common and best-studied demyelinating visual occurrence in multiple sclerosis. However, other nondemyelinating visual disturbances also seen in the general population may be erroneously interpreted as being part of the underlying disease. This comparison has not been documented and may be helpful to overcome such difficulties.

SUMMARY

Based on clinical history and some strategies of ophthalmologic examination, physicians can achieve the correct diagnosis. Some clinical situations, however, may be challenging and a multidisciplinary approach in the care of multiple sclerosis is warranted.

Validation of the "Six Step Spot Test" for gait among patients with multiple sclerosis in Brazil

The clinical manifestations of multiple sclerosis (MS) are variable among patients, and the course of disease is not linear. Different symptoms are presented, with gradual accumulation of disability. These variations are difficult to quantify in clinical practice, and several studies have attempted to create instruments capable of measuring these disabilities. The Six Step Spot Test (SSST) was developed for quantitative evaluation of the lower limbs (LL) over time. Performance in this test reflects the complexity of sensory-motor function, including LL strength, spasticity, coordination and balance, going beyond vision and cognition. The aim of the present study was to validate the SSST in a population of MS patients in Brazil. This prospective study included 75 patients with MS, with EDSS 0 to 6.5 in the study group. Ninety-one healthy subjects were randomly selected for the control group. The results showed that the groups were similar, and that the SSST is a reliable and reproducible test. According to the statistical analysis on the data in this study, the SSST is a valid, reliable and reproducible tool for use in the Brazilian MS patient population.

The changing demographic pattern of multiple sclerosis epidemiology

The uneven distribution of multiple sclerosis (MS) across populations can be attributed to differences in genes and the environment and their interaction. Prevalence and incidence surveys could be affected by inaccuracy of diagnosis and ascertainment, and prevalence also depends on survival. These sources of error might play a part in the geographical and temporal variations. Our literature search and meta-regression analyses indicated an almost universal increase in prevalence and incidence of MS over time; they challenge the well accepted theory of a latitudinal gradient of incidence of MS in Europe and North America, while this gradient is still apparent for Australia and New Zealand; and suggest a general, although not ubiquitous, increase in incidence of MS in females. The latter observation should prompt epidemiological studies to focus on changes in lifestyle in females. New insights into gene-environment and gene-gene interactions complicate interpretations of demographic epidemiology and have made obsolete the idea of simple causative associations between genes or the environment and MS.