Geographical Distribution of Myasthenia Gravis in Northern Europe - Results from a Population-Based Study from Two Countries

Abstract

Objectives: To compare the prevalence of myasthenia gravis (MG) subgroups based on immunological markers and clinical presentation in two geographically complete MG populations in northern Europe. Methods: This cross-sectional study included all living MG patients in Norway and a regional cohort from the Netherlands. Patients were identified using their hospital registration codes. Medical charts of subjects >16 years were reviewed. Inclusion criteria were clinical MG, a positive antibody test for acetylcholine receptor (AChR MG) or muscle-specific kinase (MuSK MG), or if seronegative MG, confirmed by an electrophysiological test. Results: 1,205 MG patients (534 Norwegians and 671 Dutch) fulfilled the criteria, giving a higher point prevalence in the Netherlands (167/million, 95% CI 155-180) than in Norway (138/million, 95% CI 126-150). In particular, rates of AChR MG (143 vs. 111/million), MuSK MG (6.5 vs. 0.5/million), and ocular phenotype (62 vs. 24/million) were higher in the Netherlands. Conclusion: Novel findings are an AChR MG geographical north-south gradient and a 2.6-fold more ocular MG patients in the Netherlands than in Norway. The MuSK MG latitudinal gradient supports the notion of a north-south gradient in Europe, with a higher prevalence in the south. The variation is probably explained by genetic differences between the populations, in addition to environmental interactions.

Lifestyle factors and disease-specific differences in subgroups of Swedish Myasthenia Gravis

“…Similar descriptions have been sparsely reported in MG, 1,2,17,18 and the main importance of this data is to make clinicians aware of disease-associated features that need to be addressed to optimize the care of MG patients. Similar descriptions have been sparsely reported in MG, 1,2,17,18 and the main importance of this data is to make clinicians aware of disease-associated features that need to be addressed to optimize the care of MG patients.…”

Diversity in mental fatigue and social profile of patients with myasthenia gravis in two different Northern European countries

“…Although myasthenia gravis (MG) is a rare disease, the majority of epidemiological studies on MG are limited to national areas, whereas one previous study has compared regions from two different European countries, Norway and the Netherlands (Boldingh et al., ). The prevalence of disease‐specific antibodies is known to vary in different regions of the world, in particular the prevalence of muscle‐specific tyrosine kinase (MuSK) antibodies (Gilhus & Verschuuren, ).…”

Myasthenia Gravis; Frequency of Different Clinical Features in Patients Presenting to a Tertiary Care Hospital, Karachi

“…Other studies have found a different age patterns of MG patients which is due to demographic variability as well as difference in selection criteria. 18 The patients which were included in our study had a relatively shorter history of the duration of myasthenia gravis. Contrary to many other studies, the mean ± SD duration of symptoms among our patients was 5.23 ± 3.52 months which ranged within 1 month to 1 year only.…”