Direct medical costs and their predictors in South Korean patients with systemic lupus erythematosus

We aimed to estimate the annual direct medical costs of South Korean systemic lupus erythematosus (SLE) patients, and their predictors. The 2010 annual direct medical costs of SLE patients in the Hanyang BAE Lupus cohort in South Korea were assessed. The information was taken directly from the hospital database and medical records, and included clinical characteristics, disease activity, organ damage, and healthcare utilization. Cost predictors were estimated with a multivariate linear regression model. A total of 749 SLE patients (92.7 % female, mean age 35.7 ± 11.3 years, mean disease duration 9.6 ± 4.9 years) were studied. Their mean annual direct medical costs amounted to USD 3305. The largest component of these costs was the cost of medication (USD 1269, 38.4 %), followed by those of diagnostic procedures and tests (USD 1177, 35.6 %). Regression analysis showed that adjusted mean SLE disease activity index score (p < 0.0001), systemic damage index (p < 0.0001), and renal (p = 0.0039) and hematologic (p = 0.0353) involvement were associated with increased direct medical costs, whereas longer disease duration was associated with lower direct medical costs. Greater disease activity and greater organ damage predict higher costs for South Korean SLE patients. Major organ involvement such as renal disorder and hematologic involvement also predicts higher costs, whereas longer duration of disease predicts lower costs.