Environmental factors could be the reason why black and south Asian people living in London have an increased risk of developing multiple sclerosis, according to a new study.
Early research led by Queen Mary University of London and Barts Health NHS Trust has found that people with those specific ethnicities have a higher prevalence of MS compared to the same groups of people in their ancestral countries.
The study, published in the Multiple Sclerosis Journal, used electronic records from general practices in four east London boroughs – Tower Hamlets, Newham, Hackney and City of London – and out of 907,151 patients registered, 776 were diagnosed with MS.
The overall prevalence of MS in east London was 111 per 100,000, but breaking those figures down into ethnicity, prevalence was established as 180 per 100,000 for the white population.
However, it was 74 per 100,000 among black people – far higher than the highest prevalence reported for any sub-Saharan African country, Ghana, where it has a prevalence of only 0.24 per 100,000 population, said study lead Dr Klaus Schmierer.
The prevalence of MS among people of south Asian origin in London was 29 per 100,000, compared with seven per 100,000 in India and five per 100,000 in Pakistan.
Dr Schmierer said although the increase could partially be explained by fewer MS diagnoses in less resourced countries, it was unlikely to explain such a massive difference.
An alternative, or additional, explanation such as increased exposure in the UK to environmental agent, or behaviours that facilitate the development, could be the reason.
“If we can clearly define the cluster of risk factors, and their proportional relevance, measures could be developed to change or remove these factors – thereby potentially eradicating MS, which is our ultimate goal,” said Dr Schmierer.
“The findings only apply to east London, and must be interpreted with caution if generalised to the rest of the UK. Due to the possibility of some people with MS being missed in GP datasets, the researchers say they are likely to have underestimated prevalence estimates by approximately a quarter, but that there is little risk for biases in data by ethnicity.
Follow-up studies are planned by the team.
Albor C, du Sautoy T, Kali Vanan N et al. Ethnicity and prevalence of multiple sclerosis in east London. Multiple Sclerosis Journal 18 March 2016; doi: 10.1177/1352458516638746
Leave a Reply