Global and Regional Trends of Multiple Sclerosis Disability-Adjusted Life Years Rates: A 25-Year Assessment

Background: Multiple sclerosis (MS) burden of disease has been described by reporting the disability-adjusted life years (DALY) index. So far, no study has assessed the trend of MS DALY rates over time. Method: Age-standardized MS DALY rates for both sexes were reported every 5 years from 1990 to 2015 in 195 countries in the Global Burden of Disease Database (GBD) database. To assess the MS DALY rates’ trends in each super region and throughout the world, we applied the Latent Growth Models. We also utilized the linear mixed model to evaluate the effect of development factor on MS DALY rates. Results: Our results showed that 5 out of 7 GBD super regions had negative trends in MS DALY rates during these years and the remaining 2 – Latin America and the Caribbean (slope = 0.196, p < 0.05) and South Asia – slope = 0.057, p > 0.05 – had upward trends. Using a linear mixed model, we found that the mean difference of MS DALY rates was about 25 DALYs higher in developed countries compared to developing ones (p < 0.0001). Conclusion: In general, our findings revealed a global downward trend in the MS DALY rate. We also conclude that MS DALY rates are decreasing both in developed and developing countries, with a steeper slope in the developed world.