Disease‐modifying therapies and T1 hypointense lesions in patients with multiple sclerosis: A systematic review and meta‐analysis

BACKGROUND: Previous research has shown that cerebral T1 hypointense lesions are positively correlated with the disability of multiple sclerosis (MS) patients. Hence, they could be used as an objective marker for evaluating the progression of the disease. Up to this date, there has not been a systematic evaluation of the effects of disease‐modifying therapies (DMTs) on this prognostic marker. OBJECTIVES: To evaluate the effects of FDA‐approved DMTs on the numbers and volume of T1 hypointense lesions in adult patients with MS. METHODS: We included studies with the mentioned desired outcomes. In March 2021, we searched MEDLINE (Ovid), Embase, and CENTRAL to find relevant studies. All included studies were assessed for the risk of bias using the RoB‐2 tool. Extracted data were analyzed using a random‐effects model. Certainty of evidence was assessed using GRADE. RESULTS: Thirteen studies with 7484 participants were included. Meta‐analysis revealed the mean difference between the intervention and comparator groups for the number of lesions was −1.3 (95% CI: −2.1, −0.5) and for the mean volume of lesions was −363.1 (95% CI: −611.6, −114.6). Certainty of evidence was judged to be moderate. Heterogeneity was considerable. DISCUSSION: DMTs reduce the number and volume of T1 hypointense lesions. Although, these findings must be interpreted cautiously due to the high values of heterogeneity.