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

Elaborating the knowledge structure and emerging research trends of physical activity for multiple sclerosis: A bibliometric analysis from 1994 to 2023

BACKGROUND

Multiple sclerosis is a common inflammatory neurological disease among young adults and is the tenth leading cause of the global burden of disease. Existing common treatments such as pharmacological and palliative therapies do not control the neurodegenerative process or cure multiple sclerosis. Numerous epidemiological surveys, randomised controlled trials, and systematic reviews with meta-analyses support the effects of physical activity on health-related outcomes among patients with multiple sclerosis. Moreover, bibliometric analysis can provide a broad evidence synthesis beyond systematic reviews and meta-analyses, allowing researchers and other stakeholders to obtain a one-stop overview of this research field. Therefore, this bibliometric analysis aims to provide insight into the knowledge structure of the field of physical activity for multiple sclerosis over the past three decades, and to predict emerging research trends.

METHODS

This study strictly complied with step-by-step guidelines of bibliometric analysis, combining performance analysis and science mapping. Four indexes from the Web of Science Core Collection were selected as data sources, and articles and review articles in the field of physical activity for multiple sclerosis from 1994 to 2023 were included in this analysis. Mircrosoft Excel, RStudio, VOSviewer 1.6.20, and CiteSpace 6.3.R1 (64-bit) Advanced were used to perform performance analysis and science mapping.

RESULTS

Over the past three decades, this field published a total of 1,271 documents, with the scientific output showing a rapid upward trend over the past two decades. Robbert W Motl was the most prolific author in this field, with a total of 300 publications. The USA contributed nearly half of the publications in this field (549 documents), and the University of Illinois System was the institution with the highest number of publications (222 documents). Multiple Sclerosis and Related Disorders was the journal that published the highest number of documents in this field (117 documents), while more than a third of this field's publications were included in the category: Clinical Neurology (438 documents). The Reference co-citation analysis identified three main research trends, including shifts in research methodology, changes in health outcomes in randomised controlled trials, and shifts in different types of physical activity interventions. Combining the results from reference co-citation analysis and citation burst analysis, the combination of behaviour change technique and telerehabilitation may be the emerging research trend.

CONCLUSION

This bibliometric analysis identifies rapid growth in the field of physical activity for multiple sclerosis over the past two decades. Moreover, the combination of performance analysis and science mapping provides insight into knowledge structure in this field and informed future research trends for researchers and the relevant stakeholders.

Living With Multiple Sclerosis: The Rainbow of Inspiring Experiences and Resilience in the Face of the Disease

INTRODUCTION

Multiple sclerosis (MS), a leading cause of disability in young adults worldwide, including in Iran, affects their whole life so common care is no longer effective. In this regard, context-based approaches should be considered for a holistic care delivery that accords with the patients' inputs. We aimed to explore patients' understanding of MS and their personal experiences of living with this disease.

METHODS

A qualitative descriptive study was conducted. The data were collected through in-depth, semi-structured interviews with 17 patients. These patients were selected using a purposive sampling method, and the data were analyzed using a conventional content analysis approach.

FINDINGS

Three main categories and nine subcategories were identified: Thunder and Lightning strike in the form of Displeasure, Social wrong beliefs, Experiences of Constraints, Interference with Life Stages and Dark Spots on the Horizon of the Future; Subtle Beam consisting of Extrinsic Light Radiation, Reflection of Individual Effort and Formation of a Rainbow by Resilience and Hope for a Bright Future.

CONCLUSION

By offering multidimensional support, patients reported a shift from fear to a vibrant life. Although research often focuses on the negative aspects of MS, this study recognizes both positive and negative aspects. These findings can contribute to future interventional research.

PATIENT OR PUBLIC CONTRIBUTION

During the explanation of research goals and consent acquisition, participants were reminded that sharing their experiences could provide valuable insights benefiting others coping with or at risk of the same disease. Additionally, during data analysis, codes extracted were reviewed and improved with active participant involvement.

The overall and smoking-attributable burden of multiple sclerosis among older adults aged 65-89 years from 1990 to 2019 and predictions to 2040

Background

The global prevalence of aging individuals with multiple sclerosis (MS) is increasing. This study aimed to assess the burden and trends of overall and smoking-attributable MS in older adults aged 65-89 years at the global, regional, and national levels.

Methods

The number and rates of years of life lived with disability (YLD) and years of life lost (YLL) due to MS for older adults in 204 countries and territories from 1990 to 2019 were retrieved from the Global Burden of Disease (GBD) Study 2019. Estimated annual percentage change (EAPC) in the age-standardized YLD and YLL rates were calculated to quantify the temporal trends. The Bayesian age-period-cohort model was used to predict the trends from 2020 to 2040.

Results

In 2019, there were an estimated 80,040 (95% uncertainty interval 57,534 to 103,608) YLD and 139,132 (107,632 to 161,172) YLL caused by MS among older adults globally. The age-standardized YLD and YLL rates decreased by an average of -0.21% (95% CI -0.26 to -0.16) and - 0.2% (95% CI -0.26 to -0.14) per year for overall MS from 1990 to 2019, respectively. The number of YLL globally in 2019 was 7,891 (5,003 to 10,991) and 15,667 (10,833 to 20,076) due to smoking-attributable MS. The age-standardized YLD and YLL rates decreased by an annual average of -1.14% (95% CI -1.25 to -1.04) and - 1.15% (95% CI -1.27 to -1.03) for MS attributable to smoking. Although the global age-standardized rates of YLD and YLL for MS among older adults declined from 1990 to 2019, many regions showed increases. The largest increase in age-standardized YLD rate of MS was observed in East Asia (average annual change 1.62% [95% CI: 1.56 to 1.68]), while the largest increase in the age-standardized YLL rate occurred in High-income North America (1.74% [1.53 to 1.96]). Nationally, the age-standardized YLD and YLL rates for overall and smoking-attributable MS increased exponentially with increases in SDI level (all model p < 0.001). Furthermore, projections have also indicated an expected decrease in the age-standardized rates of YLD and YLL of MS in the elderly population from 2020 to 2040.

Conclusion

Tracking trends in MS burden among older adults provides insights into the potential shifts in disease patterns over time. The findings lay the groundwork for informed decision-making in public health and healthcare delivery, aiming to ensure that older adults with MS receive appropriate care and support.

The consequences of delayed diagnosis and treatment in persons with multiple sclerosis given autologous hematopoietic stem cell transplantation

OBJECTIVES

We have analyzed the association of delayed both diagnosis and treatment of persons with MS with the long-term results of patients given autologous hematopoietic stem cell transplantation (aHSCT).

METHODS

Patients with MS referred to the HSCT-Mexico program were included in the study; in 103, detailed pre- and post-transplant evolution could be recorded. Two groups of patients were analyzed according to the time of evolution between the onset of symptoms and the definite diagnosis of MS: more than 8 months (delayed diagnosis, DD), or less than 8 months (non-delayed diagnosis, NDD). The progression of MS was assessed by changes in the expanded disability status scale (EDSS).

RESULTS

The time elapsed between the onset of symptoms and the correct diagnosis was lower for the NDD group (1.55 vs. 35.87 months, p<0.05). Both groups of patients showed a similar EDSS score at diagnosis (1.5 vs. 1.5); however, the EDSS at the time of the transplant was higher in the DD group (4.5 vs. 3.0, p=0.3) and the response of the EDSS score to the transplant was significantly better for the NDD group, the last EDSS scores being 2.5 vs. 4.25 (p=0.03). Both groups of patients responded to aHSCT by diminishing the EDSS, but the response was significantly better in the NDD group.

CONCLUSIONS

These data indicate that both the pre-transplant progression of the disease and the response to aHSCT were significantly worse in the DD group. An early diagnosis and an early aHSCT intervention are critical for a good prognosis, in terms of lowering and stabilizing the motor disability in MS patients given autografts.

Gender differences in the burden of multiple sclerosis in China from 1990 to 2019 and its 25-year projection: An analysis of the Global Burden of Diseases Study

Background and Aims

Multiple sclerosis (MS) is a crippling, chronic, gender-related disease that causes burdens to individuals and society. China has a considerable and increasing population of MS. We aim to analyze the gender disparities in the burden of MS in China and predict the trends.

Methods

The study was conducted based on the Global Burden of Disease Study 2019. Data on incidence, prevalence, deaths, and disability-adjusted life years (DALYs) of MS in China from 1990 to 2019 was descriptively analyzed by year, gender, and age group. The Nordpred package in R (version 4.2.2) was used for age-period-cohort analysis to predict the all-ages numbers and age-standardized rates of incidence, prevalence, deaths, and DALYs in China from 2020 to 2044.

Results

The number of prevalent cases of MS in 2019 reached 18,143.56 (95% uncertainty intervals [UI]: 13,997.71-22,658.60) in males and 24,427.11 (95% UI: 18,906.02-30,530.21) in females in China. The peak age of prevalence was shifted from 40-44 years in 1990 to 45-49 years in 2019 in females but remained unchanged in males. In contrast to the increased age-standardized prevalence rate, the age-standardized death rate (ASDR) and age-standardized DALYs rate showed downward trends, which were more significant in females. Different from the global, Chinese males showed lower prevalence but higher deaths and DALYs than females for age-standardized rates and numbers. In the next 25 years, the patient population will remain large and peak around 44,599.78 in 2025-2029. The ASDR, age-standardized DALYs rate, and DALYs number were expected to decrease. The improvements in deaths and DALYs will be more significant in females.

Conclusion

Males with MS had a lower prevalence but higher deaths and DALYs than females in China. The ASDR and age-standardized DALYs rate have reduced over the past 30 years and were expected to continue decreasing, especially in females. The burden of MS will remain notable in the next 25 years.

Segmental and global longitudinal strain measurement by 2-dimensional speckle tracking echocardiography in severe rheumatic mitral stenosis

BACKGROUND

The present study aimed to detect subtle left ventricular (LV) dysfunction in patients with severe rheumatic mitral stenosis (MS) by measuring global and segmental longitudinal strain with a two-dimensional speckle tracking echocardiography (2D-STE) method.

METHODS

In this case-control study, 65 patients with severe rheumatic MS and preserved ejection fraction (EF ≥ 50% measured by conventional echocardiographic methods) were compared with 31 otherwise healthy control subjects. All patients underwent LV strain measurement by the 2D-STE method in addition to conventional echocardiography using a VIVID S60 echocardiography device.

RESULTS

Absolute strain values in myocardial segments 1-8, 10, and 12 (all basal, mid anterior, mid anteroseptal, mid inferior, and mid anterolateral segments) were significantly lower in patients with severe MS compared with the control group (P < 0.05 for all). The absolute global longitudinal strain (GLS) value was higher in the control group (-19.56 vs. -18.25; P = 0.006). After adjustment for age, gender, and systolic blood pressure, the difference in GLS between the two groups was as follows: mean difference=-1.16; 95% CI: -2.58-0.25; P = 0.110.

CONCLUSION

In patients with severe rheumatic MS and preserved EF, the absolute GLS tended to be lower than healthy controls. Furthermore, the segmental strain values of LV were significantly lower in most of the basal and some mid-myocardial segments. Further studies are warranted to investigate the underlying pathophysiology and clinical implications of this subclinical dysfunction in certain segments of patients with severe rheumatic MS.

A burden shared: the financial, psychological, and health-related consequences borne by family members and caregivers of people with cancer in India

In India, approximately 1.4 million new cases of cancer are recorded annually, with 26.7 million people living with cancer in 2021. Providing care for family members with cancer impacts caregivers' health and financial resources. Effects on caregivers' health and financial resources, understood as family and caregiver "financial toxicity" of cancer, are important to explore in the Indian context, where family members often serve as caregivers, in light of cultural attitudes towards family. This is reinforced by other structural issues such as grave disparities in socioeconomic status, barriers in access to care, and limited access to supportive care services for many patients. Effects on family caregivers' financial resources are particularly prevalent in India given the increased dependency on out-of-pocket financing for healthcare, disparate access to insurance coverage, and limitations in public expenditure on healthcare. In this paper, we explore family and caregiver financial toxicity of cancer in the Indian context, highlighting the multiple psychosocial aspects through which these factors may play out. We suggest steps forward, including future directions in (1) health services research, (2) community-level interventions, and (3) policy changes. We underscore that multidisciplinary and multi-sectoral efforts are needed to study and address family and caregiver financial toxicity in India.

Quality of life of MS patients in Trinidad and Tobago: Anomaly or adaptation?

BACKGROUND AND OBJECTIVE

There has been growing interest in quality of life associated with multiple sclerosis but the research has been overwhelmingly carried out in developed countries. This study aimed to assess quality of life of multiple sclerosis patients in Trinidad and Tobago.

METHODS

All multiple sclerosis patients were asked to complete demographic, EQ-5D-5L and MSQOL-54 questionnaires. EQ-5D data were compared with population norms for Trinidad and Tobago. MSQOL-54 data were compared with results from a matching cohort of non-MS respondents. Regression analyses were used to explore the association between MSQOL-54 scales and EQ-5D utility.

RESULTS

The 97 patients were mainly urban, highly educated and 75% female. EQ-5D-5L data showed more frequent and more severe problems and lower index values than the population and patients of other chronic illness clinics in Trinidad and Tobago. MSQOL-54 results showed that patients were more affected by physical items, but had high scores on mental and emotional items when compared with the matching cohort and patients in other countries.

CONCLUSION

The low prevalence and demographics of patients suggest the possibility of undetected cases in rural areas and/or among less educated groups. Further investigation into the high levels of mental and emotional health among patients may lead to the design of interventions to help patients of multiple sclerosis and other illnesses.

Epidemiology of multiple sclerosis in the Campania Region (Italy): Derivation and validation of an algorithm to calculate the 2015-2020 incidence

OBJECTIVE

We aim to validate an algorithm based on routinely-collected healthcare data to detect incidence of multiple sclerosis (MS) in the Campania Region (South Italy) and to explore its spatial and temporal variations.

METHODS

We included individuals resident in the Campania Region who had at least one MS record in administrative datasets (drug prescriptions, hospital discharge, outpatients), from 2015 to 2020. We merged administrative to the clinical datasets to ascertain the actual date of diagnosis, and validated the minimum interval from our study baseline (Jan 1, 2015) to first MS records in administrative datasets to detect incident cases. We used Bayesian approach to explore geographical distribution, also including deprivation index as a covariate in the estimation model. We used the capture-recapture method to estimate the proportion of undetected cases.

RESULTS

The best performance was achieved by the 12-month interval algorithm, detecting 2,150 incident MS cases, with 74.4% sensitivity (95%CI = 64.1%, 85.9%) and 95.3% specificity (95%CI = 90.7%, 99.8%). The cumulative incidence was 36.68 (95%CI = 35.15, 38.26) per 100,000 from 2016 to 2020. The mean annual incidence was 7.34 (95%CI = 7.03, 7.65) per 100,000 people-year. The geographical distribution of MS relative risk shows a decreasing east-west incidence gradient. The number of expected MS cases was 11% higher than the detected cases.

CONCLUSIONS

We validated a case-finding algorithm based on administrative data to estimate MS incidence, and its spatial/temporal variations. This algorithm provides up-to-date estimates of MS incidence, and will be used in future studies to evaluate changes in MS incidence in relation to different risk factors.

A Systematic Review and Meta-Analysis of the Brief Cognitive Assessment for Multiple Sclerosis (BICAMS) International Validations

Cognitive impairment is a prevalent and debilitating symptom of multiple sclerosis (MS) but is not routinely addressed in clinical care. The Brief Cognitive Assessment for Multiple Sclerosis (BICAMS) was developed in 2012 to screen and monitor MS patients’ cognition. This systematic review and meta-analysis aimed to identify, synthesise, and critically appraise current BICAMS’ international validations. The literature search was conducted using PubMed, PsycINFO and Web of Science electronic databases in August 2022. Quantitative, peer-reviewed adult studies, which followed the BICAMS international validation protocol and were published in English, were included. The search identified a total of 203 studies, of which 26 were eligible for inclusion. These reported a total of 2833 adults with MS and 2382 healthy controls (HC). The meta-analysis showed that BICAMS identified impaired cognitive functioning in adults with MS compared to HC for all three subtests: information processing speed (g = 0.854, 95% CI = 0.765, 0.944, p < 0.001), immediate verbal recall (g = 0.566, 95% CI = 0.459, 0.673, p < 0.001) and immediate visual recall (g = 0.566, 95% CI = 0.487, 0.645, p < 0.001). Recruitment sites and strategies limit the generalisability of results. BICAMS is a valid and feasible international MS cognitive assessment.

Global, regional, and national burden of multiple sclerosis from 1990 to 2019: Findings of global burden of disease study 2019

BACKGROUND

The global rising prevalence and incidence of multiple sclerosis (MS) has been reported during the past decades. However, details regarding the evolution of MS burden have not been fully studied. This study aimed to investigate the global, regional, and national burden and temporal trends in MS incidence, deaths, and disability-adjusted life years (DALYs) from 1990 to 2019 using the age-period-cohort analysis.

METHODS

We performed a secondary comprehensive analysis of incidence, deaths, and DALYs of MS by calculating the estimated annual percentage change from 1990 to 2019 obtained from the Global Burden of Disease (GBD) 2019 study. The independent age, period, and birth cohort effects were evaluated by an age-period-cohort model.

RESULTS

In 2019, there were 59,345 incident MS cases and 22,439 MS deaths worldwide. The global number of incidences, deaths, and DALYs of MS followed an upward trend, whereas the age-standardized rates (ASR) slightly declined from 1990 to 2019. High socio-demographic index (SDI) regions had the highest ASR of incidences, deaths, and DALYs in 2019, while the rate of deaths and DALYs in medium SDI regions are the lowest. Six regions which include high-income North America, Western Europe, Australasia, Central Europe, and Eastern Europe had higher ASR of incidences, deaths, and DALYs than other regions in 2019. The age effect showed that the relative risks (RRs) of incidence and DALYs reached the peak at ages 30-39 and 50-59, respectively. The period effect showed that the RRs of deaths and DALYs increased with the period. The cohort effect showed that the later cohort has lower RRs of deaths and DALYs than the early cohort.

CONCLUSION

The global cases of incidence, deaths, and DALYs of MS have all increased, whereas ASR has declined, with different trends in different regions. High SDI regions such as European countries have a substantial burden of MS. There are significant age effects for incidence, deaths, and DALYs of MS globally, and period effects and cohort effects for deaths and DALYs.

Helicobacter pylori infection and risk of multiple sclerosis: An updated meta-analysis

BACKGROUND

There is considerable controversy around the question as to whether Helicobacter pylori (H. pylori) infection has a protective or causative role in the development of multiple sclerosis (MS). This study evaluated published information to assess the association between H. pylori infection and MS.

METHODS

We conducted a comprehensive systematic review of relevant observational studies in international databases. A random-effects model was used to calculate pooled odds ratio (OR) and 95% confidence interval (CI). I² statistic was used to assess the between-study heterogeneity. Subgroup and meta-regression analyses were applied to identify the source of heterogeneity.

RESULTS

In total, 22 studies (25 datasets) were eligible for the meta-analysis: 17 datasets had prevalence data and eight datasets had data on the mean titer of anti-H. pylori IgG. The pooled prevalence of H. pylori was 44.1% (908/2606) in the MS patients and 46.1% (1016/2200) in the controls, indicating a non-significant protective effect of H. pylori on MS (OR, 0.82; 95%CI, 0.58-1.17). In the subgroup analysis, studies that used ELISA yielded a significant protective association (OR, 0.59; 95%CI, 0.46-0.77), while a positive non-significant association (OR, 1.33; 95%CI, 0.83-2.15) was found from studies that used other serological methods; interestingly, a significant positive association (OR, 6.64; 95%CI, 2.40-13.76) was found from studies that used histological methods to detect H. pylori infection.

CONCLUSIONS

Our findings do not support the hypothesis that H. pylori infection represents a protective factor against the development of MS; however, the results varied depending on the diagnostic method(s). Particularly, a significant positive association was identified when studies introduced results based on histological examination, suggesting that active H. pylori infection might be a risk factor for development of MS. Thus, further studies are needed utilizing accurate diagnostic methods to elucidate the association between active H. pylori infection and MS.

Epstein-Barr virus, interleukin-10 and multiple sclerosis: A ménage à trois

Multiple Sclerosis (MS) is an autoimmune disease that is characterized by inflammation and demyelination of nerve cells. There is strong evidence that Epstein-Barr virus (EBV), a human herpesvirus infecting B cells, greatly increases the risk of subsequent MS. Intriguingly, EBV not only induces human interleukin-10 but also encodes a homologue of this molecule, which is a key anti-inflammatory cytokine of the immune system. Although EBV-encoded IL-10 (ebvIL-10) has a high amino acid identity with its cellular counterpart (cIL-10), it shows more restricted and partially weaker functionality. We propose that both EBV-induced cIL-10 and ebvIL-10 act in a temporally and functionally coordinated manner helping the pathogen to establish latency in B cells and, at the same time, to balance the function of antiviral T cells. As a result, the EBV load persisting in the immune system is kept at a constant but individually different level (set point). During this immunological tug of war between virus and host, however, MS can be induced as collateral damage if the set point is too high. Here, we discuss a possible role of ebvIL-10 and EBV-induced cIL-10 in EBV-driven pathogenesis of MS.

Autoreactive lymphocytes in multiple sclerosis: Pathogenesis and treatment target

Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS) characterized by destruction of the myelin sheath structure. The loss of myelin leads to damage of a neuron’s axon and cell body, which is identified as brain lesions on magnetic resonance image (MRI). The pathogenesis of MS remains largely unknown. However, immune mechanisms, especially those linked to the aberrant lymphocyte activity, are mainly responsible for neuronal damage. Th1 and Th17 populations of lymphocytes were primarily associated with MS pathogenesis. These lymphocytes are essential for differentiation of encephalitogenic CD8⁺ T cell and Th17 lymphocyte crossing the blood brain barrier and targeting myelin sheath in the CNS. B-lymphocytes could also contribute to MS pathogenesis by producing anti-myelin basic protein antibodies. In later studies, aberrant function of Treg and Th9 cells was identified as contributing to MS. This review summarizes the aberrant function and count of lymphocyte, and the contributions of these cell to the mechanisms of MS. Additionally, we have outlined the novel MS therapeutics aimed to amend the aberrant function or counts of these lymphocytes.

Anlotinib attenuates experimental autoimmune encephalomyelitis mice model of multiple sclerosis via modulating the differentiation of Th17 and Treg cells

BACKGROUND

In multiple sclerosis (MS), the imbalance between T helper (Th)-17 cells and regulatory T (Treg) cells are critical in autoimmune central nervous system (CNS) inflammation and demyelination. Experimental autoimmune encephalomyelitis (EAE) is an established mouse MS model and simulates MS at diverse levels.

OBJECTIVES

This study aims at investigating the impact of anlotinib on the clinical severity of EAE and CD4⁺ T cell differentiation.

MATERIALS AND METHODS

EAE-induced mice were treated with water (control) or 6 mg/kg anlotinib by gavage daily. At the peak of EAE, histopathological examination and flow cytometry analysis of CNS-infiltrating CD4⁺ T cells were performed. In vitro differentiation of CD4⁺ T cells under different conditions was detected by flow cytometry and quantitative real-time PCR. Finally, the impacts of anlotinib on the phosphorylation of signal transducer and activator of transcription 3 (STAT3) and the transcription levels of key genes involved in Th17 and Treg differentiation were tested.

RESULTS

Anlotinib attenuated the clinical severity of EAE and changed the frequencies of CNS-infiltrating CD4⁺ T cell subsets. Anlotinib inhibited the differentiation of Th17 cells in vitro, decreased the phosphorylation of STAT3, and reduced the expression of Rorc. Anlotinib promoted the differentiation of Treg cells and upregulated the expression levels of CD39 and CD73.

DISCUSSION AND CONCLUSIONS

Anlotinib alleviated the symptoms of EAE via inhibiting the Th17 cell differentiation and promoting Treg cell differentiation. Our study provides new opportunities for the exploitation of anlotinib as a therapeutic agent for the treatment of MS.

A Quantitative Synthesis of Eight Decades of Global Multiple Sclerosis Research Using Bibliometrics

Bibliometric studies on the field of multiple sclerosis (MS) research are scarce. The aim of this study is to offer an overarching view of the body of knowledge about MS research over eight decades–from 1945 to 2021–by means of a bibliometric analysis. We performed a quantitative analysis of a massive dataset based on Web of Science. The analysis included frequencies, temporal trends, collaboration networks, clusters of research themes, and an in-depth qualitative analysis. A total of 48,356 articles, with 1,766,086 citations were retrieved. Global MS research showed a steady increase with an annual growth rate of 6.4%, with more than half of the scientific production published in the last decade. Published articles came from 98 different countries by 123,569 authors in 3,267 journals, with the United States ranking first in a number of publications (12,770) and citations (610,334). A co-occurrence network analysis formed four main themes of research, covering the pathophysiological mechanisms, neuropsychological symptoms, diagnostic modalities, and treatment of MS. A noticeable increase in research on cognition, depression, and fatigue was observed, highlighting the increased attention to the quality of life of patients with MS. This bibliometric analysis provided a comprehensive overview of the status of global MS research over the past eight decades. These results could provide a better understanding of this field and help identify new directions for future research.

The trend analysis of neurological disorders as major causes of death and disability according to human development, 1990-2019

This study aims to assess the trends in the incidence rate of neurological disorders in developed and developing countries worldwide during 1990-2019. The age-standardized incidence rate (per 100000 persons) of neurological disorders was the primary outcome, extracted from the Global Burden of Disease database for 189 countries and territories from 1990 to 2019. Using the Human Development Index (HDI), countries were classified into developed (HDI ≥ 0.7) and developing (HDI < 0.7) groups. Longitudinal analysis was performed using the Latent Growth Model (LGM) to assess the change in the incidence rate of neurological disorders over time in these groups. In developed countries, the most increasing rate is related to depressive disorders, with a rising rate of 40.15 in 100000 every five years (p = 0.001). Alzheimer's and dementia, Parkinson and multiple sclerosis are in the next rank, with increasing rates of 8.77, 1.24, and .02, respectively (all p < 0.001). Over time, the significant decreasing trend has been determined related to conducting disorder, attention-deficit and hyperactivity, meningitis, anxiety, and eating disorders, with the rates of - 13.92, - 4.96, - 2.7, - 1.6, and - 1.44, respectively (all p < 0.05). In developing countries, meningitis, conduct disorder, attention-deficit and hyperactivity, stroke, and autism spectrum showed a significant decreasing trend over time, with rates of - 15.45, - 5.84, - 2.56, - 1.86, and - 1.07, respectively (all p < 0.05). Headache disorder has the most increasing rate of 79.5, following depressive (rate 35.32), substance use (rate 14.99), anxiety (rate 7.18), and eating (rate 3.4) disorders. Also, Alzheimer's and dementia, bipolar disorder, schizophrenia, Parkinson's, brain and central nervous system cancer, and multiple sclerosis are in the next rank and had significant increasing trends (all p < 0.05). Given the high economic and social burden of neurological disorders, the rate of these diseases in most countries does not seem to have dropped remarkably. The heterogeneous incidence rate in some world countries seems to be due to underestimating and gaps in epidemiological information. It is necessary to provide exact registry systems for health policies, especially in developing countries.

Incidence of Pediatric Multiple Sclerosis in Iran within 2000-2019

OBJECTIVES

Due to a lack of data on pediatric multiple sclerosis (MS) epidemiology in Iran, this study aimed to determine the incidence rate of pediatric MS in Iran.

MATERIALS & METHODS

 All the data of the patients with MS registered in the Ministry of Health and Medical Education of Iran for 20 years were collected in this study; those born in 1982 and diagnosed with the disease and treated since 2000 were included in this study. Therefor The collected variables were patients' age at the time of diagnosis, gender, year of diagnosis, urban or rural residency, and province of residence. Additionally, age-specific incidence rates per 100,000 of the population were calculated.

RESULTS

This study was performed on 4544 cases of pediatric MS within 2000-2019, of which 997 patients (21.9%) were male. The mean age of the patients with MS at the time of diagnosis was 14.3±4.6 years, and 4414 children (97.1%) lived in urban areas. The incidence rate of pediatric MS in Iran during 20 years increased from 0.26 per 100,000 of the population in 2000 to 1.53 in 2019.

CONCLUSION

The incidence of pediatric MS in Iran is high, and the development of diagnostic practices in the past decade in Iran has contributed to the detection of this high incidence.

Association between water and sanitation, air and emission pollution and climate change and neurological disease distribution: A study based on GBD data

Along with the urbanization and industrialization of countries, the prevalence of chronic diseases has increased. There is ample evidence that ambient pollution can play a major role in these diseases. This study aimed to investigate the association between neurological disorders (NDs) and their subtypes with environmental factors. In this country-level study, we used the age-standardized prevalence and incidence rate (per 100,000 populations) of NDs and its subtypes that have been taken from the Global Burden of Disease (GBD) database in 2019. We used correlation and regression analysis to assess the association between variables. Also, multivariable regression analysis was performed to identify the most important variables in NDs distribution. Age-adjusted NDs incidence rate was significantly higher in developed countries compared to developing countries (11345.25 (95% CI: 11634.88-11055.62) and 9956.37 (95% CI: 10138.66-9774.08)). Association results indicated that the impact of water and sanitation could be more effective than air pollution on NDs. The increase in water and sanitation index levels was positively correlated with NDs incidence rate and prevalence (regression coefficient (b) = 38.011 (SE = 6.50) and b = 118.84 (SE = 20.64), p < 0.001, respectively) after adjusting socio-economic and demographic factors. Furthermore, the incidence of NDs was negatively correlated with the increase in air quality (b = -16.30 (SE = 7.25), p = 0.008). Water and sanitation and their related factors are plausible factors in the distribution of NDs, which may be linked to the potential role of air and water pollution, such as heavy metals and particle matters. These results can be used by politicians and municipal service planners for future planning.

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

OBJECTIVES

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).

METHODS

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.

RESULTS

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.

CONCLUSION

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.