Predictors of relapse severity in multiple sclerosis

Background The severity of relapses is one of the determinants of residual disability in multiple sclerosis (MS), contributing to the final progressive state. However, the factors that predict the severity of relapses are not fully understood. Aim To predict relapse severity in MS and investigate the relationship between relapse severity and the degree of improvement in physical, cognitive, and social tests. Methods This observational single-center study prospectively assesses relapse severity in patients with MS. Relapses were classified as mild, moderate, and severe. Before relapse treatment and 1 month into remission four physical tests, four cognitive tests, and six surveys were performed. Multinomial regression analyses were applied to predict relapse severity. Results A total of 126 relapses were studied prospectively. Twenty-two were lost to follow-up. Multiple sclerosis International Quality of Life (MusiQol) questionnaire ( r = 0.28, p = 0.006) and Symbol Digit Modalities Test (SDMT, r = 0.23, p = 0.022) improvement statuses were correlated with the severity of the relapse. Higher cases with improvement were observed in the severe relapse group on both MusiQol and SDMT, but no difference for those with a mild relapse. In the predictive model, only disease duration [Odds Ratio (OR) 0.808 95% confidence ınterval (CI) 0.691 to 0.945; p = 0.008] and Body Mass Index (BMI, OR 1.148 95% CI 1.018 to 1.294; p = 0.024) were associated with relapse severity. Conclusion Only disease duration was found to be predictive of relapse severity among disease-related variables. On the other hand, BMI may be a modifiable patient-related factor to consider in the management of exacerbations in MS.