The prevalence of multiple sclerosis (MS) in the US is nearly double previous estimates.

MS is a chronic auto-immune disease that is usually diagnosed in younger adults, typically between ages 15–60 years.

In 2016, GlobalData estimated that the US had around 400,000 diagnosed prevalent cases.

However, new data from a study conducted by Mitchell T Wallin et al (and supported by the US National MS Society) found that 10-year MS prevalent cases in the US are almost twice as high as previously reported cases, at an estimated 727,344 people in 2017.

MS estimates for the US

The new MS estimates for the US was published in the journal Neurology in February 2019.

This study mitigated several data limitations in our current understanding of MS in the US. First, the study extracted patient claims data from six healthcare systems in the US (Optum , Truven Health Market Scan, Kaiser Permanente Southern California, Department of Veterans Affairs, Medicaid and Medicare) in order to mitigate the lack of a centralised medical record system in the US.

Second, due to the chronic relapsing nature of MS, many patients in the US could go years without being seen by a doctor and thus are not counted in short-term medical record-based epidemiological studies. This study accounted for the underestimation by analysing data over a three-year period and projecting to 10-year prevalence.

This new estimate put US MS prevalence at around 0.3% of the general population, which is on par with that of Canada and other Northern European markets.

The implications of this new finding include that the MS burden in the US is much higher than previously thought and that MS patients in the US may not be getting adequate care. Since MS is a disease that gets worse over time, regular doctor visits are essential even if the patient is not on disease-altering treatments.

MS prevalence estimates in the 16MM, compared with new US data

Source: GlobalData
Notes: 16MM = Australia, Brazil, Canada, China, France, Germany, India, Italy, Japan, Mexico, Russia, South Africa, South Korea, Spain, the UK and the US.