Differences in the autoantibody phenotypes and long-term outcomes between juvenile- and adult-onset systemic sclerosis.

[Objective] To investigate differences in autoantibodies, clinical features, and long-term outcomes between juvenile- and adult-onset systemic sclerosis (SSc). [Methods] Autoantibodies and survival rates over a maximum of 20 years were retrospectively analyzed in 504 Japanese patients with SSc (juvenile-onset SSc, n=17; adult-onset SSc, n=487) using data from Kyoto University Registry. [Results] The autoantibodies observed were anti-topoisomerase-I (71% vs. 26%), anti-centromere (24% vs. 54%), and anti-RNA-polymerase-III (0% vs. 12%). A diffuse type and multi-organ involvement were observed in patients with anti-topoisomerase-I in both juvenile- and adult-onset SSc. In patients with anti-centromere, a diffuse type (juvenile-onset SSc vs. adult-onset SSc, 75% vs. 28%) and pulmonary fibrosis (50% vs. 17%) were more frequently observed in juvenile-onset SSc than in adult-onset SSc. Cox-proportional hazard analyses showed that older onset (hazard ratio: 1.06, 95% confidence interval: 1.03-1.09) was associated with death, while autoantibodies were not significantly associated with death. Cumulative survival rates for 20 years were similar between juvenile- and adult-onset SSc when classified based on the presence of anti-centromere (100% vs. 89%, p=0.20) and anti-topoisomerase-I (90% vs. 90%, p=0.70). [Conclusions] Juvenile-onset SSc had more frequent diffuse-type and anti-topoisomerase-I. An older onset was slightly associated with mortality, whereas autoantibodies were not associated with mortality.