Progression of MS Among an Aging New York State Population

Background: Multiple sclerosis (MS) is an autoimmune disease that initially affects young adults at the peak of their productivity and careers. Disease course and duration are considered to be the strongest predictors for disability progression in MS. However, prospective data suggests that older age may be the only established linear predictor of greater disability. By identifying features that may be predictive of stable disease vs. disease progression, among an aging MS population, we can advance our understanding of MS disease progression.  

Objectives: To identify risk factors associated with stable MS course over time.

Methods: This is a retrospective study including subjects enrolled in New York State MS Consortium (NYSMSC), the oldest comprehensive longitudinal population-based dataset available in the United States. In order to be included in our study, the participant had to be at least 60 years old at his or her most recent follow-up, have a disease duration of ≥15 years, have been in the NYSMSC database for ≥5 years and have at least 3 follow-ups. Two comparison groups will be ascertained; a stable vs. a worsening disease group based on Kurtzke Expanded Disability Status Scale (EDSS) scores changes after 5 years (worsening scores >1 for baseline EDSS <6.0 and >0.5 for baseline EDSS ≥6.0). Use of disease modifying therapies as well as variables such as: patient employment, sex, race, education, living environment, insurance status and patient-reported outcome variables, using the LIFEware instrument, will be investigated for association with disease progression. We will conduct χ² and independent samples t-tests to examine associations between variables and potential covariates.  Logistic regression modeling will be used to test differences and independent effects of covariates.

Results: Of the 400 participants in our dataset ≥60 years old who have been in the NYSMSC database for at least 5 years with a disease duration ≥15 years, 202 (50.5%) had a worsening of EDSS scores after 5 years. Mean age at symptom onset = 55.8 (SD=7.1) and mean disease duration to date is 18.4 years (SD=10.2). There were no differences between those who worsened and those who remained stable with regards to age at symptom onset, age at diagnosis or disease duration.

Conclusions: By providing essential information about predictors of MS disease course, this study will advance understanding of MS progression and improve quality of life for elderly patients with MS.