Multiple sclerosis prevalence in England doubles due to better diagnosis

Multiple sclerosis (MS) has more than doubled in recorded prevalence in England from 2000 to 2020, increasing by 6% per year, largely due to improved diagnosis and longer life expectancy, finds a new study by University College London (UCL) and Imperial College London researchers.

The team 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.

In the study published in JAMA Neurology, the researchers estimate that 190,000 people are living with MS in England today.

People with MS are living longer than ever before, thanks to better care, disease-modifying therapies, and earlier diagnosis, but there is still much more to do.

We found that quitting smoking and maintaining a healthy weight were both associated with lower mortality. Therefore, tackling smoking, obesity, and inequalities in access to diagnostics and care could reduce avoidable deaths and help people with MS stay healthier for longer."

Professor Olga Ciccarelli, Lead Author, NIHR Research Professor of Neurology, UCL Queen Square Institute of Neurology

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.

The researchers reviewed over 30 years of public health records, using a very large database of primary (GP) 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 standardised 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% per year. Extrapolating that trend forward, the researchers 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 researchers say this suggests that people in deprived areas are more likely to be living with undiagnosed MS, while 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, and as smoking and obesity rates are higher in deprived areas, this may be contributing to inequalities in MS outcomes.

First author Professor Raffaele Palladino (Imperial College London and University of Naples Federico II) said: "While much progress has been made in improving MS diagnosis and access to treatments that extend lifespans and improve quality of life, there is still more work to be done. Efforts to improve earlier diagnosis should be particularly focused on reaching socioeconomically disadvantaged groups who might face greater barriers to diagnosis and care."

Dr Catherine Godbold, Senior Research Communications Manager at the MS Society, commented: "Exploring the role of deprivation in MS outcomes is important research. It's encouraging to see evidence showing improvements in life expectancy for people with MS. But we need to see more consistent access to diagnosis, treatment, and support for people to manage their symptoms so that everyone with MS, whatever their circumstances or where they live, can live well. We know smoking and obesity can worsen MS, and this study suggests targeted support around stopping smoking and maintaining a healthy weight could also be crucial in reducing inequalities in MS outcomes."

The study was supported by the National Institute for Health and Care Research (NIHR), the MS Society, and the NIHR UCLH Biomedical Research Centre.