A-B) Effect of host factors on microbiome beta-diversity was measured using the ADONIS test of unweighted and weighted UniFrac distances. Analysis was restricted to subjects with complete demographic information and a recorded BMI, (n = 38 HC, n = 135 RRMS, n = 31 progressive MS) C) Microbiota altered in RR or progressive MS vs. healthy control, MaAsLin, adjusted for age, BMI, sex, race, and ethnicity. D-F) Abundance of the two most decreased taxa and two most increased taxa in both RRMS and progressive MS vs. HC (D), unique to RRMS (E), or unique to progressive MS (F). * p < 0.05, ** p < 0.01, ***p < 0.001.