AFUICAN-AMERICAN RACE AND ANTIBODIES TO TOPOISOMERASE-I ARE ASSOCIATED WITH INCREASED SEVERITY OF SCLERODERMA LUNG-DISEASE

Study objectives: To determine whether African-American race is indepe ndently associated with lung disease in scleroderma. Design: Retrospec tive review. Setting: University medical center in Baltimore. Patients : One hundred one patients with diffuse cutaneous scleroderma with ava ilable serum samples. Measurements: Patients underwent lung function t esting as part of their routine clinical care. Percent predicted value s adjusted for race were calculated for FVC, single-breath carbon mono xide diffusing capacity (DCO), and FEV1. Serum samples were assayed fo r the presence of antibodies to topoisomerase I and RNA polymerase II. Results: Scleroderma patients of African-American race had lower perc ent predicted values than white patients for FVC (p < 0.002), DCO (p < 0.0001), and FEV, (p<0.0001). Antibodies to topoisomerase I but not a ntibodies to RNA polymerase II were also associated with lung function . African-American scleroderma patients were distinct from white patie nts in having younger age of onset and higher prevalence of antibodies to topoisomerase I. In multivariate analyses accounting for sex, age, smoking history, years of scleroderma symptoms, and RNA polymerase II antibody status, African-American race and topoisomerase I antibody s tatus independently predicted lower lung function. Conclusion: African -American race and antibodies to topoisomerase I are independent risk factors for scleroderma lung disease.