Multiple Sclerosis Mortality Rates Elevated in Armed Forces

Deaths from multiple sclerosis (MS) are higher among men in the armed forces, new findings show.

While analyzing trends in occupational mortality in England and Wales, investigators observed elevated mortality rates among this subpopulation. In response, the investigators sought to document and examine potential explanations for this trend in a study published in Occupational Medicine.

The investigators analyzed data on the underlying cause of death and last full-time occupation for approximately 3.7 million deaths among men aged 20 to 74 years in England and Wales during 1979 and 2010.

After proportional mortality ratios (PMRs) were calculated and standardized for age, the investigators compared PMRs for men with MS in the armed forces with those for each main social class and in selected other occupations.

PMRs for MS were also compared with those for motor neuron disease (MND).

The results of the study showed that of the 26,507 deaths among men whose last recorded occupation was the military, a total of 7485 deaths were from MS—including 129 in the armed forces—showing an overall PMR of 243. Furthermore, the excess became even more pronounced in each of the decades of study, with PMRs ranging from 220 to 259, and across the entire age range.

Elevation of PMRs for MS were not raised to the same extent in the comparator occupations nor any of the main social classes. There was no parallel increase in PMRs for MND, according to the report.

“These findings suggest that the high proportional mortality from MS in British military personnel is unlikely to have occurred by chance, or as an artefact of the method of investigation,” the authors concluded. “However, the only military cohort study with published results on MS does not support an increased risk. It would be useful to analyze data on MS from other established military cohorts, to check for evidence of a hazard.”

An estimated 2.5 million individuals worldwide are living with MS. Females are more likely to have the disease than men, and about 2 to 3 times more common in relapsing-remitting MS.

“Given the suspicions raised by our analysis, we suggest that there is now a case for re-analyzing data from other military cohorts that are already under follow-up, to check whether they give any support to the possibility of occupational hazard,” the authors wrote.