A prospective study of survival and prognostic indicators of systemic lupus erythematosus in a southern Chinese population

Abstract

Objectives. To study the survival rate and prognostic indicators of systemic lupus erythematosus (SLE) in a southern Chinese population. Methods. One hundred and eighty-six patients with SLE diagnosed between 1992 and 1999 were prospectively followed. Clinical features at presentation, subsequent evolving features, autoantibody profile, damage scores and mortality data were obtained. Prognostic factors for survival were studied by statistical analysis. Results. One hundred and sixty-three female and 23 male SLE patients were studied. The female to male ratio was 7.1 to 1 and the mean age at presentation was 33.6 yr (range 12-75). The mean disease duration was 45.2 months. At diagnosis, arthritis, malar rash and alopecia were the commonest features. During follow-up, the prevalence of nephritis, arthritis, photosensitivity and haematological disease increased significantly. Thirty-one per cent of the patients had organ damage at the time of data analysis and renal disease was the commonest cause. Logistic regression revealed that central nervous system disease, discoid lesions and treatment with high-dose steroid were independent predictors for damage. Nine patients died during the study period (three of disease-related complications and six of infections). The 3-, 5-, and 7-yr survival rates of our cohort were 97, 93 and 93%, respectively. Cox regression analysis revealed that thrombocytopenia and high-dose steroid treatment were independent risk factors for mortality. Conclusions. The survival of SLE in our southern Chinese patients is similar to that of the Caucasian series reported in the 1990s. Although nephritis contributes to organ damage, it is not a major determinant for survival. Infection remains the commonest cause of death. High-dose steroid treatment and thrombocytopenia are independent risk factors for mortality. Judicious use of immunosuppressive agents is necessary to improve the short-term survival of SLE.