Air pollution could be a risk factor for the development of multiple sclerosis (MS), a new study conducted in Italy has found.
The research, presented at the European Academy of Neurology (EAN) Virtual Congress, detected a reduced risk for MS in individuals residing in rural areas that have lower levels of air pollutants known as particulate matter (PM). It showed that the MS risk, adjusted for urbanisation and deprivation, was 29% higher among those residing in more urbanised areas.
The study sample included over 900 MS patients within the region, and MS rates were found to have risen 10-fold in the past 50 years, from 16 cases per 100,000 inhabitants in 1974 to almost 170 cases per 100,000 people today. Whilst the huge increase can partly be explained by increased survival for MS patients, this sharp increase could also be explained by greater exposure to risk factors.
The analysis was conducted in the winter, given that this is the season with the highest pollutant concentrations, in the north-western Italian region of Lombardy, home to over 547,000 people.
Commenting on the findings at the EAN Virtual Congress, lead researcher Professor Roberto Bergamaschi explained, “It is well recognised that immune diseases such as MS are associated with multiple factors, both genetic and environmental. Some environmental factors, such as vitamin D levels and smoking habits, have been extensively studied, yet few studies have focused on air pollutants. We believe that air pollution interacts through several mechanisms in the development of MS and the results of this study strengthen that hypothesis.”
