Evaluating the risk of ischemic stroke at a young age in patients with autoimmune inflammatory rheumatic diseases: a population-based cohort study in Taiwan.

Background: Recent studies have demonstrated an increased incidence of ischemic stroke among patients with certain autoimmune inflammatory rheumatic diseases (AIIRDs). However, the associations between young stroke and AIIRDs have not been fully investigated. This study aimed to evaluate the risk of ischemic stroke among young patients with AIIRDs.

Methods: The National Health Insurance Research Database in Taiwan was utilized to establish cohorts of patients with AIIRDs diagnosed between 2004 and 2015, who were compared with 1,000,000 control participants. Cox proportional hazards regression models were used to calculate the hazard ratio of ischemic stroke and young ischemic stroke for individual AIIRDs after adjustment for relative risk factors.

Results: During the study period, a total of 64,120 patients with AIIRDss and 1,000,000 control patients were identified. The overall mean follow-up time was 5.33 years. There were 223 (0.8%) and 1,923 (0.3%) young ischemic stroke-related hospitalizations among patients with AIIRDs and controls, respectively. The incidence rate of young ischemic stroke was 0.08 in patients with rheumatoid arthritis, 0.08 in patients with Sjögren's syndrome, 0.26 in patients with systemic lupus erythematosus, 0.17 in patients with idiopathic inflammatory myositis, 0.24 in patients with systemic sclerosis, 0.05 in patients with Behçet's disease, and 0.44 in patients with systemic vasculitis, versus 0.05 per 100 person-years in the general population. The adjusted hazard ratios for young ischemic stroke were 1.07 (95% CI 0.70-1.43) for rheumatoid arthritis, 1.39 (95% CI 0.94-2.06) for Sjögren's syndrome, 5.79 (95% CI 4.68-7.17) for systemic lupus erythematosus, 2.07 for idiopathic inflammatory myositis (95% CI 0.98-4.38), 2.79 for systemic sclerosis (95% CI 1.38-5.63), 0.82 for Behçet's disease (95% CI 0.26-2.55), and 4.15 (95% CI 1.96-8.82) for systemic vasculitis.

Conclusions: Patients younger than 50 years with systemic lupus erythematosus, systemic sclerosis, or systemic vasculitis have a significantly elevated risk of developing ischemic stroke. Further research is needed to elucidate the pathogenesis of accelerated atherosclerosis in these AIIRDs.