March 18, 2016

expert reaction to study investigating the role of environmental factors and ethnicity in the prevalence of multiple sclerosis

A study looking at the prevalence of multiple sclerosis (MS) in different ethnic groups has been published in the Multiple Sclerosis Journal. The authors report higher prevalence in the white population compared to the black and South Asian populations of the same area of east London, which was in turn higher than the prevalence of MS in Africa and South Asia.

Dr Sorrel Bickley, Head of Biomedical Research at the MS Society, said:

 “More than 100,000 people in the UK have MS and we welcome research that helps us better understand the risk of a person developing the condition.

“This study furthers existing knowledge that the prevalence of MS differs significantly between ethnic groups, but we still don’t know whether that’s due to environmental factors [as suggested in the press release] or other things, like how easy it is for someone to receive an MS diagnosis.

“Within the paper the researchers acknowledge the poor quality of international data on MS prevalence; they helpfully set out how they could investigate true environmental risk in future. We look forward to seeing the results of these studies.

“While this paper provides a local insight into MS it does not yet present any robust evidence to suggest that people should change their behaviours or where they choose to live. We’ll be following future work on this with interest.”

Prof. Daniel Altmann, Professor of Immunology, Imperial College London, said:

“Research breakthroughs have led to substantial advances in treatment options over the past decade for people with MS. Meanwhile, the causes of this disease are an enduring conundrum: this is a disease of genetic risk plus environment, but it has been hard to get clear ideas of what is encompassed here by the term ‘environment’. It has long been held that MS is more common in populations of Northern Europe and Northern America than in people living in more temperate regions.

“This new study uses analysis of East London MS patients to put hard numbers to a trend that had long been suspected: in people of South Asian or Afro-Caribbean origin living in London, there is an acquired risk of disease, many times higher than seen in the countries of origin. This points the finger very clearly at their changed environment. This offers a clear framework for new studies to dissect which lifestyle and environment changes are at work.

“While this study encompasses a relatively small, geographical catchment area, it’s highly likely that it can be extrapolated more widely. The study builds on related observations that have been made in Bradford and in France. The big challenge is to pin down the environmental impacts: clearly, many things may change, including UV exposure, childhood infections, microbial environment and diet.”

‘Ethnicity and prevalence of multiple sclerosis in east London’ by Albor et al. will be published in Multiple Sclerosis Journal on Friday 18th March. 

Declared interests

Dr Sorrel Bickley: No conflicts of interest to declare.

Prof. Daniel Altmann: No conflicts of interest to declare.