Predictors of secondary progressive multiple sclerosis in a real word retrospective cohort: the role of clinical factors and disease-modifying therapy patterns.

INTRODUCTION

Identification of predictors associated with progression to Secondary progressive multiple sclerosis (SPMS) remains clinically important for optimizing long-term disease management. We aimed to evaluate demographic, clinical, and disease-modifying therapy (DMT)-related factors associated with progression to SPMS in a real-world cohort of patients with MS.

METHODS

In this retrospective cohort study, 650 MS patients diagnosed between 2013 and 2019 were enrolled and followed until 2024. Demographic characteristics, clinical variables and DMT history were compared between patients with benign MS and those who progressed to SPMS. Multivariate Cox regression analysis was performed to identify independent predictors of progression to SPMS.

RESULTS

About 12.3% of patients developed SPMS. Male sex (p ≤ 0.001), Current age (p ≤ 0.001), longer disease duration (p ≤ 0.001), higher baseline and current Expanded Disability Status Scale (EDSS) (p ≤ 0.001), increased relapse frequency and hospitalization (p ≤ 0.001), diagnostic delay (p = 0.012), polysymptomatic onset (p = 0.05), and DMT switching (p ≤ 0.001) were significantly associated with SPMS conversion. In multivariate analysis, diagnostic delay [HR 1.14 (95% CI 1.07-1.20), p < 0.001], baseline EDSS [HR 1.22 (95% CI 1.07-1.40), p = 0.003], and current EDSS [HR 1.94 (95% CI 1.74-2.16), p < 0.001] independently predicted the risk of progression to SPMS.

CONCLUSION

Progression to SPMS was associated with several demographic and clinical factors, particularly delayed diagnosis and higher disability burden. Early diagnosis and prompt initiation of effective treatment strategies may play a critical role in reducing long-term disability progression in MS patients.