Multiple Sclerosis Causes Twice as Many Deaths for British Military Personnel

Details of a British study, published in June in the journal of Occupational Medicine, ‘Mortality from multiple sclerosis in British military personnel’, has shown that British soldiers, sailors and airmen are almost twice as likely to die from multiple sclerosis (MS), when compared with other occupations.[1]

MS is an incurable neurological condition, caused by a destructive immune system, which attacks the protective tissue (myelin sheath) surrounding nerves. This disrupts and slows the transmission of chemical and electrical messages along the neural pathway. Consequently, symptoms can include loss of physical and sensory function, additional to an average life expectancy reduction of between 7 and 9 years.[2]

Currently, it is believed that MS affects more than 100,000 in the UK alone, including 2 to 3 times more women than men. Further, the autoimmune disease is understood to be triggered by a combination of genetic and environmental factors, such as exposure to infections which relate to the Epstein Barr virus, smoking and vitamin D deficiency.

The latest investigation, undertaken by the Medical Research Council (MRC) and Health and Safety Executive (HSE), saw scientists examine the death certificates of 3.7 million men, aged between 20 and 74, over a 31 year period with a view to finding a link between the prevalence of MS as a cause of death and employment type.[3]

For those whose most recent employment was in a British military role, the risk of contracting and dying from MS was much greater. From 1979 to 2010, out of a total 7485 recorded MS-related deaths, 129 were last hired by the military, yielding a proportional mortality rate (PMR) of 243:

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What is more, deaths were most common for service men in the age bracket of 45-59:


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Although the reasoning behind the occupational disease relationship was left unexplained in the study, the author was certain of the fact that ‘the consistency and statistical significance of the excess indicate that it is most unlikely to have occurred simply by chance’ and ‘was unlikely to be the result of fewer deaths from other causes, such as heart disease, or by factors related to social class’.

Instead, it has been inferred that an ‘unidentified occupational hazard’ may be the root cause of ‘elevated proportional mortality ... in each of three successive decades’.

As was mentioned above, infectious disease may be legitimate cause of MS and, speculating on the conditions of British armed forces recruits, the study implies that:

... the close proximity in which military recruits live and work might facilitate the transmission of one or more infections that trigger later MS’.

In the UK, the figures collated were consistent for each decade, across the 31 years, showing similar PMR. This differs from previous US studies, as those indicated a mortality spike for military workers who served in the Gulf War between 1990 and 1991.[4]

The Ministry of Defence has called for more research to be conducted in order to establish preventative measures, given the findings were suggestive of an increased risk of death, attributed to MS. This will undoubtedly require analysis of data from other established military cohorts.

We will continue to report on any developments in this area in future BCDN editions.

 

 

[1] E. C. Harris, et al., ‘Mortality from multiple sclerosis in British military personnel’, Occupational Medicine <https://academic.oup.com/occmed/article/doi/10.1093/occmed/kqx083/3872312/Mortality-from-multiple-sclerosis-in-British> accessed 17 August 2017.

[2] ‘Multiple Sclerosis’ (NHS Choices 17 February 2016) <http://www.nhs.uk/conditions/Multiple-sclerosis/Pages/Introduction.aspx> accessed 17 August 2017.

[3] Kat Lay, ‘Military personnel more likely to die from multiple sclerosis’ (17 August 2017 The Times) <https://www.thetimes.co.uk/article/military-personnel-more-likely-to-die-from-multiple-sclerosis-7wrkqwsg2> accessed 17 August 2017. 

[4] Kat Lay, ‘Military personnel more likely to die from multiple sclerosis’ (17 August 2017 The Times) <https://www.thetimes.co.uk/article/military-personnel-more-likely-to-die-from-multiple-sclerosis-7wrkqwsg2> accessed 17 August 2017.