Association of socioeconomic disadvantage and neighborhood disparities with clinical outcomes in multiple sclerosis patients

Background: Socioeconomic disadvantage may be an important contributor to clinical outcomes in MS but is not well understood. Our objective was to examine the associations between Area Deprivation Index (ADI), a validated measure of neighborhood-level disadvantage, with clinical outcomes. Methods: We assessed the longitudinal association between MS Performance Test (MSPT) and quality of life in Neurological Disorders (Neuro-QoL) measures with ADI quartiles (Q1: lowest deprivation - Q4 highest deprivation) in relapsing remitting MS (RRMS) and progressive MS cohorts. Results: Our study included 2,921 patients (65.8% RRMS and 34.1% progressive MS) with 13,715 visits. Patients living in the most disadvantaged areas had almost universal worsening on baseline MSPT and Neuro-QoL scores (p < 0.05) when compared to patients living in areas of lowest deprivation. Manual Dexterity Test (MDT) illustrated particular disparity as RRMS patients living in the greatest area of deprivation had MDT score which averaged 2.9 seconds longer than someone living in areas of least deprivation. Longitudinal analysis illustrated less favorable MSPT and Neuro-QoL outcomes across visits between Q1 versus Q4 ADI quartiles within in the RRMS cohort but not within the progressive MS cohort. After adjustment, linearly increasing area deprivation scores reflected less favorable Processing Speed Test (PST) and six Neuro-QoL outcomes among the RRMS cohort. Within the progressive cohort, higher deprivation was associated less favorable MDT, PST and 11 of 12 NeuroQoL outcome measures. Conclusions: This study provides evidence for socioeconomic disadvantage as a risk factor for disability accrual in MS and may be targeted to improve care while informing resource allocation.