Correlation between MRI utilization and therapy switches in disease-modifying treatments for multiple sclerosis.

Background and objectives: Studies measuring the role of magnetic resonance imaging (MRI) in therapeutic decision-making are rare in people with multiple sclerosis (pwMS). This study aimed to measure the association between MRI utilization and disease-modifying therapy (DMT) switches in pwMS.

Methods: This retrospective cohort study identified pwMS in 2018 from a de-identified national claims database. PwMS who received MRI in 2018 were compared to pwMS not receiving MRI in 2018. PwMS were observed for six months to assess the incidence of DMT switches.

Results: The study sample consisted of 11,972 pwMS. 3,931 (32.8%) pwMS received at least one MRI in 2018. Overall, MRI utilization increased the odds of switching DMT (OR = 1.49, 1.79, and 3.01 for 1, 2, and ≥ 3 CNS locations imaged). For those on injectable or platform DMT, any MRI utilization increased the odds of switching DMT (OR = 1.54, 2.00, and 3.48 for 1, 2, and ≥ 3 locations imaged). For those on oral DMT, only receiving MRI of 2 or ≥ 3 locations increased the odds of a DMT switch (OR = 1.36, 1.89, and 2.40 for 1, 2, and ≥ 3 locations). Finally, for pwMS on infusible therapies, there was little evidence that MRI changed the odds of a DMT switch.

Discussion: Among pwMS on injectable or oral DMT, imaging more CNS locations increased the odds of switching DMT after adjusting for age and relapse incidence. For pwMS on high-efficacy infusible DMTs, MRI did not change the odds of switching DMT but remains essential for safety monitoring.