Multiple sclerosis has more than doubled in recorded prevalence in England from 2000 to 2020, increasing by 6 percent per year, largely because of improved diagnosis and longer life expectancy, according to a new study. The authors found that survival of people with MS improved significantly over time thanks to advances in treatments and care, although they also identified inequalities, with higher mortality in deprived areas. 

MS is a neurological condition in which the immune system attacks the central nervous system. Most people are diagnosed between the ages of 20 and 50, but the first signs of MS can start years earlier. Common early signs include tingling, numbness, limb weakness, and problems with vision, but it can take time to reach a definitive diagnosis.

University College London and Imperial College London researchers reviewed more than 30 years of public health records, using a very large database of primary care records in England from 1990 to 2023, some of which were also linked to secondary (hospital) care data. They identified possible MS cases based on multiple sources including diagnostic records and prescription of drugs that are exclusively used to treat MS.

They estimated that standardized prevalence (how common MS is across the population, adjusted for differences in age, sex, and region) increased from 107 per 100,000 people in 2000 to 232 per 100,000 in 2020. This corresponded to an estimated 131,000 people living with MS in 2020. In adjusted analyses, prevalence increased by 6 percent per year. Extrapolating that trend forward, the study’s authors project that approximately 190,000 people are likely living with MS in England today.

The researchers also found that survival improved through the study period, as people are living longer with MS after diagnosis. Those diagnosed later in the study period were more likely to live to 80 years old and had lower annual mortality rates.

Mortality was found to be highest in deprived areas, while prevalence was highest in the least deprived areas. The authors said this suggests that people in deprived areas are more likely to be living with undiagnosed MS. The evidence also suggests they have lower access to care, may be accessing treatments later on in the disease course, and are more likely to be living with other health conditions.

The researchers highlight that smoking and obesity both contribute to poor outcomes for MS. As smoking and obesity rates are higher in deprived areas, this may be contributing to inequalities in MS outcomes.

The study was published in the journal JAMA Neurology.