Generational changes in multiple sclerosis phenotype in North African immigrants in France: A population-based observational study

Abstract

BackgroundThe incidence of multiple sclerosis (MS) changes from generation to generation in ethnically different immigrants compared with native-born people. We aimed to determine whether there are generational changes in MS phenotypes among North African immigrants in France.MethodsCohort study with data from a population-based MS registry to compare the clinical characteristics of 80 first (NAG1) and 167 second (NAG2) generation North Africans with MS living in France with 5200 native-born Europeans. Adjusted Cox models were used to test the association between scores of 3 and 6 on the expanded disability status scale (EDSS) and the “origin/generation” variable.ResultsCox models for EDSS scores 3 and 6 showed a higher risk of score 3 (hazard ratio = 1.738, 95% confidence interval 1.237 to 2.444; P = .002) and 6 (hazard ratio = 2.372, 95% confidence interval 1.626 to 3.462; P<.0001) for NAG1 than Europeans. Being NAG2 was not significantly associated with higher hazards of scores 3 and 6.ConclusionsWe found two different phenotypes among NAG1 and NAG2 MS patients in France. NAG1, but not NAG2, have a higher risk of disability than Europeans. This raises the question of environmental factors in MS expression, and advocates appropriate patient management according to generation in immigrants.

Asian and African/Caribbean AQP4-NMOSD patient outcomes according to self-identified race and place of residence

“…Despite these limitations, this same issue of racial groups has also been examined in another demyelinating condition -multiple sclerosis. It has been shown that African patients have a worse visual and overall prognosis and that place of residence seems to be protective, which is in line with our findings for NMOSD (Aurencao et al, 2016;Merle et al, 2005;Naismith et al, 2006;Nardin et al, 2018).…”

Clinical and MRI characteristics of multiple sclerosis in patients of Middle Eastern and North African ancestry residing in Ontario, Canada

“…Other studies have demonstrated higher disability accumulation rates in MENA-MS patients versus EUR-MS patients residing in France, 13,14 with a generational effect on disease severity. 15 The generational effect was also observed in our study, but it is important to note that our study was not powered to assess such an effect making it difficult to draw definitive conclusions. It is unclear to what extent the immigration process, other socioeconomic determinants, and the different environmental exposures change disease phenotype in this population, and further study is warranted.…”

“…13,14 Furthermore, first-generation MS patients of MENA descent (MENA-MS) immigrants have a more aggressive disease course than second-generation MENA-MS patients, suggesting a generational effect on MS phenotype. 15 Generally, there is a dearth of information detailing the clinical course of immigrating MENA-MS patients and the published data remain inconclusive. 9,13,16 Canada has a large proportion of immigrants from diverse countries, with a relatively large population of immigrants originating from MENA countries, making it an ideal location to study the intersection of genetics, environment, and their effect on disease phenotype in specific populations.…”

“…13,14 Furthermore, first-generation MS patients of MENA descent (MENA-MS) immigrants have a more aggressive disease course than second-generation MENA-MS patients, suggesting a generational effect on MS phenotype. 15…”

High prevalence of comorbidities at diagnosis in immigrants with multiple sclerosis

“…Immigrants may encounter unique barriers in accessing mental healthcare due to language difficulties, lack of health system literacy, and stigma toward mental health problems in their communities 27 , 28 Third, clinicians should follow these patients closely and consider early intervention as mental health conditions have been associated with greater long-term disability in MS, and immigrants and non-White persons may already be at risk for earlier disability accumulation. 31 – 33 In a large population-based cohort study of incident MS cases in Canada, psychiatric comorbidity was associated with subsequent greater accrual of neurologic disability as measured by the Expanded Disability Status Scale (EDSS). 26 Another large cohort study in Sweden found that persons having MS with depression had a higher risk of reaching major disability milestones, including EDSS scores of 3.0, 4.0, and 6.0.…”