Systemic lupus erythematosus (SLE) has been associated with increased risk of tuberculosis (TB). However, little is known about the extent and risk factors for TB among Asian patient with SLE. We aimed to assess the rate of TB in patients with SLE, and investigate the risk of SLE on TB development using hospital administrative database. This is an historical cohort study of hospital discharge database from 2004 to 2011 to identify cases with SLE and TB using International Statistical Classification of Diseases and Related Health Problems, 9th Revision, Australian Modification (ICD-9-AM) codes. Of 301568 hospitalized patients, 841 (0.3%) patients had SLE, 1843 (0.6%) patients had TB, including 17 SLE patients (2.0%). SLE patients had a significantly higher rate of TB (2.0 vs. 0.6%, p < 0.001) compared to that of patients without SLE. The differences in the higher rate after breaking down was in the pulmonary TB group (1.7 vs. 0.5%, p < 0.00) but not in extrapulmonary TB group (0.4 vs. 0.1%, p = 0.060). Logistic regression analyses showed that SLE was a significant and independent predictor of TB (odds ratio 4.6, 95% CI 2.8-7.5, p < 0.001) after adjustment for factors such as age group, gender, ethnicity, admission class, nutritional deficiency, organ transplantation, and Charlson comorbidity index. SLE patients were found to experience higher rates of tuberculosis in this group of Asian patient population. Patients with SLE should be considered as a high-risk group for TB, active screening for latent patients and treatment for positive TB patients is needed.
Keywords: ICD-9-AM; Risk factor; SLE; TB.