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. 2011 Jan 27;6(1):e14606.
doi: 10.1371/journal.pone.0014606.

The epidemiology of multiple sclerosis in Scotland: inferences from hospital admissions

Adam E Handel  1 , Lynne Jarvis, Ryan McLaughlin, Anastasia Fries, George C Ebers, Sreeram V Ramagopalan
Affiliations

The epidemiology of multiple sclerosis in Scotland: inferences from hospital admissions

Adam E Handel et al. PLoS One. .

Abstract

Background: Multiple sclerosis (MS) is a neurological disorder with a highly characteristic disease distribution. Prevalence and incidence in general increase with increasing distance from the equator. Similarly the female to male sex ratio increases with increasing latitude. Multiple possible risk factors have been hypothesised for this epidemiological trend, including human leukocyte antigen allele frequencies, ultraviolet exposure and subsequent vitamin D levels, smoking and Epstein-Barr virus. In this study we undertook a study of medical records across Scotland on an NHS health board level of resolution to examine the epidemiology of MS in this region.

Methods and results: We calculated the number and rate of patient-linked hospital admissions throughout Scotland between 1997 and 2009 from the Scottish Morbidity Records. We used weighted-regression to examine correlations between these measures of MS, and latitude and smoking prevalence. We found a highly significant relationship between MS patient-linked admissions and latitude (r weighted by standard error (r(sw)) = 0.75, p = 0.002). There was no significant relationship between smoking prevalence and MS patient-linked admissions.

Discussion: There is a definite latitudinal effect on MS risk across Scotland, arising primarily from an excess of female MS patients at more Northerly latitudes. Whether this is a true gradient or whether a threshold effect may apply at particular latitude will be revealed only by further research. A number of genetic and environmental factors may underlie this effect.

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Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Figure 1
Figure 1. Scatter plots of MS admission rates against latitude.
(A) Overall data. (B) Male (blue) and female (red) specific data.
Figure 2
Figure 2. Scatter plots of MS admission rates against smoking prevalence.
(A) Overall data. (B) Male (blue) and female (red) specific data.
Figure 3
Figure 3. Scatter plots of female-to-male sex-ratio of MS admission rates against latitude.
See this image and copyright information in PMC

References

    1. Noseworthy JH, Lucchinetti C, Rodriguez M, Weinshenker BG. Multiple sclerosis. N Engl J Med. 2000;343:938–952. - PubMed
    1. Alonso A, Hernán MA. Temporal trends in the incidence of multiple sclerosis: a systematic review. Neurology. 2008;71:129–135. - PMC - PubMed
    1. Staples J, Ponsonby A, Lim L. Low maternal exposure to ultraviolet radiation in pregnancy, month of birth, and risk of multiple sclerosis in offspring: longitudinal analysis. BMJ (Online first) 2010 - PMC - PubMed
    1. Handel AE, Giovannoni G, Ebers GC, Ramagopalan SV. Environmental factors and their timing in adult-onset multiple sclerosis. Nat Rev Neurol. 2010;6:156–166. - PubMed
    1. Koch-Henriksen N, Sorensen PS. The changing demographic pattern of multiple sclerosis epidemiology. Lancet Neurol. 2010;9:520–532. - PubMed

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