In progressive-onset multiple sclerosis (MS), superimposed relapses are associated with a lower risk of confirmed disability progression, according to a recent study. Researchers conducted an observational cohort study from MSBase, an international database. From 44,449 patients at time of extraction, 1,419 eligible patients (31.9%) were identified for analysis. Inclusion criteria consisted of primary progressive MS (PPMS) or progressive-relapsing MS (PRMS), adult-onset disease, and minimum data set (including ≥3 visits with disability recorded, ≥3 months between second and last visit). They found:

• Patients with PRMS were younger than those with PPMS (mean [SD] age, 46 [15] vs 51 [10] years) and demonstrated a mean lower Expanded Disability Status Scale score (mean [SD] score, 4.0 [3] vs 4.5 [2.5]) at inclusion.
• The ratio of men to women was similar in the PRMS and PPMS groups (252:301 vs 394:472).
• The overall mean (SD) age was 48 (11) years for men and 50 (10) years for women.
• Likelihood of confirmed disability progression was lower in patients with superimposed relapses (HR 0.83).