New Zealand Brain Research Institute

Author Of 1 Presentation

Epidemiology Poster Presentation

P0498 - The effect of national disease modifying therapy subsidy policy on long-term disability outcomes in people with multiple sclerosis (ID 1652)

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Disease-modifying therapies (DMT), which modify, mediate or suppress the immune system, are a major medication class for treating people with relapsing-onset multiple sclerosis (MS). However, our knowledge about these medications is largely limited to their short-term effects.


To determine: 1) the impact of national-level DMT subsidy policy on DMT use and disability in people living with MS (PwMS); and 2) the long-term effects of DMT on disability (EDSS and MSSS) and quality of life (EQ5D5L utility score).


This project was an ecological, observational cohort study comparing populations in Australia and New Zealand with similar demographics, but markedly different levels of DMT use 10-20 years post-diagnosis. Differences between countries were assessed using standardized differences (Cohen’s d), phi coefficient and Cramer’s V. Associations were assessed with univariable and multivariable (mediation) linear regression models.


We recruited 328 Australian participants, 93.9% of whom had been treated with DMT, and 256 New Zealand participants, 50.4% of whom had been treated with DMT. The Australian cohort had a longer median treatment duration (148 vs 0 months), greater proportion of disease course treated (86% vs 0%), and shorter time between diagnosis and first DMT (3 vs 24 months). The Australian cohort also had lower median EDSS (3.5 vs 4.0) and MSSS (3.05 vs 3.71), and higher quality of life (0.71 vs 0.65) at follow-up. In multivariable models, differences in DMT use significantly mediated the effect of country on disability and quality of life.


This large ecological study provides evidence for the impact of national level policy on DMT use and subsequent disability outcomes in PwMS. It also demonstrates that the protective effect of DMT may mediate the effect of national policy on disability progression and quality of life 10-20 years post-diagnosis in people with relapsing-onset MS.