Identifying disability level in multiple sclerosis patients in a U.S.-based health plan claims database

Area of Science:

• Neurology
• Health Economics
• Data Science

Background:

• Multiple sclerosis (MS) disability is typically measured by the Kurtzke expanded disability status scale (EDSS) in clinical trials.
• EDSS is not routinely captured in U.S. clinical care, limiting real-world outcome analysis.
• A need exists for a claims-based measure to assess MS disability in routine U.S. healthcare settings.

Purpose of the Study:

• To develop a claims-based disability score (CDS) for multiple sclerosis (MS).
• To utilize U.S. health plan claims and electronic medical records (EMRs) for disability assessment.
• To validate the CDS by examining healthcare costs associated with different disability levels.

Main Methods:

• Retrospective cohort study of MS patients in the U.S. (2012-2016).
• Development of the CDS using adjudicated claims and ambulatory EMR data over a 1-year baseline period.
• Analysis of all-cause healthcare costs by baseline disability level (mild, moderate, severe) to validate the CDS.

Main Results:

• Over half of the 45,687 patients in the full sample had mild disability at baseline.
• Healthcare costs were 15% higher for moderate and 20% higher for severe disability compared to mild disability (p<.0001).
• Disease-modifying therapy costs constituted a significant portion of outpatient pharmacy costs across all disability levels.

Conclusions:

• The CDS is the first claims-based MS disability measure using EMR data.
• This novel score enables outcome examination in the absence of standard EDSS markers.
• While formal EDSS validation was not possible, economic findings support the CDS's utility in reflecting disability-associated healthcare costs.