Disability progression in the absence of relapses is less common in pediatric MS than in adults with MS, according to data covering more than 5,000 patients with relapsing forms of MS. Emilio Portaccio, MD, and colleagues examined the role of progression independent of relapse activity (PIRA) and relapse-associated worsening (RAW) in 6-month confirmed disability accumulation in pediatric-onset (POMS) versus adult-onset MS (AOMS). They also assessed potential predictors of both forms of disability progression and
whether disease-modifying therapies (DMTs) reduced these events among 5,169 patients. A similar proportion of patients with POMS and AOMS experienced no (58.5% vs 54.3%), one (26.6% vs 27.9%), or two or more (14.9% vs 17.8%) confirmed disability events. However, PIRA was significantly less common in children compared with adults, and relapse-independent progression accounted for a significantly smaller proportion of disability worsening events in POMS than in AOMS (47.8% vs 66.7%). Longer exposure to DMTs significantly decreased the risk for PIRA in both groups.