Associations of multiple sclerosis with macrovascular disease risks: a retrospective cohort study using a nationwide claims database

Population-based evidence evaluating cardiovascular and cerebrovascular risks in multiple sclerosis (MS) remains limited. In this study, we investigated the association between MS and macrovascular risk differs between patients with MS and matched individuals without MS in Taiwan. This retrospective cohort study was conducted using data from nationwide database in Taiwan. The study cohort comprised 1285 patients receiving a new diagnosis of MS between 2003 and 2020. Each patient was matched with five control individuals by age, sex, insured salary, urbanization, Charlson comorbidity index, related comorbidities, and year of inclusion. A covariate-adjusted Cox proportional-hazards model was used to assess macrovascular risk in patients with MS. Adjusted hazard ratios (aHRs) and corresponding 95% confidence intervals (CIs) were calculated. In addition, a subgroup analysis by MS severity was performed to confirm the association between MS and macrovascular risk. MS severity was assessed by the history of MS-related hospitalization and the ratio of hospitalization duration to total follow-up time, categorized into mild, moderate, and severe groups. After covariate adjustment, macrovascular risk was significantly higher in the patient group than in the control group (cardiovascular disease, aHR: 1.81 [95% CI 1.28–2.57]; cerebrovascular disease, aHR: 3.34 [95% CI 2.81–4.23]). The subgroup analysis revealed that this risk was markedly higher in patients with severe MS (cardiovascular disease, aHR: 2.77 [95% CI 1.69–4.56]; cerebrovascular disease, aHR: 5.09 [95% CI 3.83–6.77]). MS was significantly associated heart failure, ischemic stroke, hemorrhagic stroke, and transient ischemic attack, but not acute myocardial infarction or atrial fibrillation. Our findings indicate a higher incidence of macrovascular events in the MS population compared with matched controls. These results highlight a potential association between MS and long-term macrovascular complications.