Clinical and Laboratory Characteristics and Mortality in Korean Patients with Systemic Sclerosis: A Nationwide Multicenter Retrospective Cohort Study

Objective. We aimed to investigate demographic and clinical features and predictors of mortality in Korean patients with systemic sclerosis (SSc). Methods. We performed a retrospective multicenter medical chart review in Korean patients diagnosed with SSc from 1986 to 2016 at 11 university hospitals representing each geographic area of Korea. SSc patients were defined according to the American College of Rheumatology preliminary classification criteria and subtyped as limited cutaneous (lcSSc) or diffuse cutaneous (deSSc) SSc. Results. We enrolled 751 patients (female, 86.7%; mean age at diagnosis, 48.9 yrs). The most common organ involvement was interstitial lung disease (52.7%), followed by gastroesophageal reflux disease (32.9%) and pulmonary arterial hypertension (13.6%). Patients with lcSSc were more common than those with deSSc (64.8 vs 35.2%), whereas anti-Scl-70 and anticentromere antibody positivity were identified in 302 (42.5%) and 175 (25.5%) patients, respectively. In the 46 (6.1%) patients who developed a malignancy, lung cancer (23.9%) was the most common diagnosis, followed by gastric (13%) and breast cancer (13%). During the study period, 57 (7.6%) patients died, and the 5- and 10-year survival rates were 94% and 87%, respectively. Increased age at diagnosis, cardiovascular involvement, and anti-Scl-70 antibody positivity were significant predictors of death. Conclusion. Clinical manifestations and survival rates in Korean SSc patients are similar to those of other populations. However, the prevalence of anti-Sc1-70 antibody is higher in Korean SSc patients compared with whites, while the prevalence of anticentromere antibody is lower.