Multiple sclerosis among Afghan immigrants in Isfahan, Iran

Prevalence and incidence of multiple sclerosis in Isfahan, Iran between 1996 and 2021: A population-based study

BACKGROUND

There has been no recent comprehensive epidemiological study on a large and stable population of multiple sclerosis (MS) in Isfahan. Therefore, we conducted this study to estimate the incidence and prevalence of MS in Isfahan province from 1996 to 2021.

METHOD

In this population-based study, we utilized the dataset from the Vice-Chancellor's Office of Isfahan University of Medical Sciences, which registers all people diagnosed with MS (PDWM) in Isfahan province, excluding those residing in Kashan city. We measured crude incidence and prevalence of MS, separated by sex, and based on age of MS onset, as well as changes in age of MS onset during observation.

RESULTS

A total of 9,909 PDWM were included in our study. The incidence during the time period of 1996-2000 was 5.4/100,000 (1.1/100,000 per year), which subsequently increased to 14.1 (2.8/100,000 per years) and 31.1 per 100,000 (6.2/100,000 per year) during 2001-2005 and 2006-2010, respectively. There was a further increase to 70.9/100,000 (14.2/100,000 per year) in 2011-2015, but it remained stable at 71.8/100,000 (12/100,000 per year) during the period of 2016-2021. In 2016, the age-standardized incidence rates of pediatric-onset, adult-onset, and late-onset MS were 1.8/100,000, 31.4/100,000, and 17.5/100,000, respectively. The prevalence of MS in 2021 was 183.9/100,000. The female/male new case ratio was 4.5 during 1996-2000, decreasing to 4.0, 3.9, 3.9, and 2.9 in the subsequent four five-year periods. The mean age of RRMS onset was 26.3 ± 8.1 between 1990 and 1999, 28.5 ± 8.3 during 2000-2009, and increased to 32.8 ± 9.6 in 2010-2019.

CONCLUSION

This study shows that Isfahan has one of the highest incidence rate and prevalence ratio of MS in the region. We observed an increase in the incidence rate during the first decade, followed by stability in the last two five- and six-year periods. Further studies are needed to identify the reasons behind the change in incidence of MS in Iran.

Ethnic disparities in the epidemiological and clinical characteristics of multiple sclerosis

BACKGROUND

Multiple Sclerosis (MS) is a neuroinflammatory disorder which affects 2.8 million people world-wide. A growing body of evidence shows ethnic disparities in MS. This review aims to evaluate differences, based upon ethnic background, in the incidence, prevalence, disease course, and efficacy of disease-modifying therapies (DMTs) among people with MS (PwMS).

METHOD

Ethnicities were classified as White, Black, Hispanic, Asian, and Middle Eastern and North African (MENA). A literature search was conducted using the PubMed search engine to identify articles on MS and ethnicity that were published in the English language between 01/01/2005 and 31/05/2022.

RESULTS

101 studies met all inclusion criteria. Although the incidence and prevalence of MS varied among ethnicities, findings were inconsistent and depended on the continent of the study. Ethnicity may have an impact on the disease course. PwMS from Black, Hispanic, and MENA, but not Asian ethnicities, appeared to accumulate physical disability at a faster rate than those from White ethnicity. Although there was a lack of studies evaluating the relative safety and efficacy of DMTs among various ethnicities, interferon-beta was found to be less efficacious in PwMS from Black ethnicity.

CONCLUSIONS

Further studies, with more uniform definitions of ethnicity are required to comprehensively understand ethnic disparities in MS, in particular to identify underlying causes, to facilitate the delivery of personalised medical care and avoid inequity.

Health condition of Afghan refugees residing in Iran in comparison to Germany: a systematic review of empirical studies

BACKGROUND

The re-emerging dominance of the Taliban in Afghanistan in 2021 caused a new wave of Afghan refugees heading Iran and neighboring countries. Iran in the Middle East and Germany in Europe are two major host countries to the largest populations of Afghan refugees. In both countries, several studies have been done to assess the health condition of refugees.

OBJECTIVES

To systematically review the existing literature to identify similarities and differences of health conditions of Afghan refugees living in the two countries, and to synthesize evidence on the health status and health care access of these populations.

METHODS

Related electronic databases and grey literature of Iran and Germany on the health of Afghan refugees were scanned and searched up for the period 2000-2020. Key terms were formed by combining "Afghan refugees or immigrants or populations or asylum seekers", "Physical or mental health", "Healthcare service or access or use", "Iran or Germany". Empirical studies were considered if they contained samples of Afghan refugees with particular outcomes for Afghans. Results were categorized for both countries in the three main areas of physical health, mental health, and access/use of healthcare services.

RESULTS

Nine hundred twenty-two documents were extracted, of which 75 full-texts were finally reviewed. 60 documents belonged to the health condition of Afghan refugees residing in Iran including 43 in physical health, 6 in mental health, 8 in healthcare access and use, and 3 in multiple aspects of health, and 15 belonged to Germany including 7 in physical health, 4 in mental health, 2 in healthcare access and use, and 2 in multiple aspects of health. A less explicit evaluation of the overall health condition of Afghan refugees was observable, particularly for Germany. While matches on the study subject exist for both countries, in comparison to Germany, we extracted more quantitative and qualitative health studies on Afghan refugees of the mentioned areas from Iran. German health studies were rare, less qualitative, and more on the health condition of diverse refugee groups in general.

CONCLUSIONS

Wide gaps and unanswered questions related to mental health and overall health status of the Afghan refugee population are observable, especially in Germany. Our systematic review identified the gap in evidence, which we would recommend to bridge using a wider lens to comprehensively assess the overall condition of refugees considering associations between health and socio-economic and cultural determinants instead of a one-dimensional approach. Further, within health studies on refugee populations, we recommend stratification of results by the country of origin to capture the within-group diversity among refugees with different countries of origin.

Multiple sclerosis epidemiology in Asia and Oceania; A systematic review and meta-analysis

BACKGROUND

Multiple sclerosis (MS) is an inflammatory demyelinating CNS disease and the most common neurological immune-mediated disorder. Due to its progressive format, it affects patients' quality of life (QoL) significantly. This study aimed to evaluate epidemiologic parameters of MS in the Asia and Oceania continents.

METHODS

A comprehensive literature search on October 1st, 2020, was performed in PubMed, Scopus, and Web of Science to retrieve original population-based studies on MS epidemiology in the Asian and Oceanian countries, published between January 1st, 1985 and October 1st, 2020. The designed search strategy was repeated for each country, and the relevant referenced articles were added to our database. A random-effect model was used to combine the epidemiological estimates, and subgroup analysis was also performed by continent, region, and country, when possible. Meta-regression analysis was done to evaluate the effects of Human Developmental Index (HDI), latitude, and study period on the epidemiologic parameters.

RESULTS

A total of 3,109 publications were found, of which 89 articles met the eligibility criteria and were included for data extraction. These articles provided data on prevalence, incidence, and mean age at disease onset in 18 countries in Asia and Oceania, including Iran, Turkey, Cyprus, Kuwait, Saudi Arabia, Qatar, UAE, Jordan, Israel, India, Malaysia, China, Hong Kong, Taiwan, Republic of Korea, Japan, Australia, and New Zealand. The pooled total prevalence, incidence, and mean age of onset in Asia and Oceania were 37.89/100000 (95% CI: 35.65 - 40.142), 2.40/100000 (95% CI: 2.22 - 2.58), and 28.21 (95% CI: 27.55 - 28.88), respectively. MS prevalence and incidence in the female gender (68.7/100000 and 4.42/100000, respectively) were infinitely higher than in the male gender (24.52/100000 and 2.06/100000, respectively). Our subgroup analysis showed that MS was much more prevalent in Australia and West Asia among the studied area. The meta-regression showed that the total incidence decreased with an increase in the HDI, and the total prevalence in Asia increased with increasing latitude gradients. Also, the study period had a positive effect on the total prevalence and incidence in Asia and Oceania.

CONCLUSION

MS prevalence and incidence have increased in recent decades. This study highlights the need for further studies to elucidate MS's geographical and temporal variations' exact etiologies.

Changing epidemiology of immune-mediated inflammatory diseases in immigrants: A systematic review of population-based studies

BACKGROUND

Immune-mediated inflammatory diseases (IMIDs) are systemic diseases of multifactorial etiology that share aberrant immune responses as the common final pathway. With rising globalization, their incidence is increasing in developing countries and among immigrants. Our primary objective was to systematically review the epidemiology of IMIDs in immigrants and conduct a meta-analysis to estimate the risk of IMIDs in immigrant populations according to their origin and destination countries.

METHODS

We systematically searched five biomedical databases and reviewed population-based studies, from inception through August 2018, that reported incidence or prevalence data of inflammatory bowel disease (IBD), multiple sclerosis (MS), type 1 diabetes (T1D), systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), ankylosing spondylitis (AS) or psoriasis and psoriatic arthritis (PPA) among immigrants and the host population.

RESULTS

The incidence and prevalence of IMIDs among immigrants differ from host populations, and evolve over subsequent generations. The risk of IBD among immigrants approximates that in hosts, especially among South Asians, with ulcerative colitis incidence changing prior to Crohn's disease incidence. MS risk is highest in Iranian immigrants, T1D in African immigrants and SLE in African and Iraqi immigrants. Data on other IMIDs are sparse. Significant heterogeneity between the studies precluded meta-analysis.

CONCLUSION

Based on our systematic review, the epidemiology of IMIDs among immigrants varies according to native and host countries, immigrant generation, and IMID type. The rapid evolution suggests a role for non-genetic factors and gene-environment interactions. Future studies should focus on these pattern shifts, given implications of rising global burden of IMIDs and immigration.