Causes and Factors Associated with Frequent Hospitalization in Chinese Patients with Systemic Lupus Erythematosus: An Ambispective Cohort Study

BACKGROUND: Hospitalizations in patients with systemic lupus erythematosus (SLE) have been reported from different regions in the world. This study aimed to evaluate the annual hospitalization rate, causes of hospitalization, and potential factors associated with frequency of hospitalization in Chinese patients. MATERIAL/METHODS: We performed an ambispective cohort study for hospitalized patients with SLE in a Chinese single center. Data on demographics, organ involvements, laboratory abnormities, clinical treatments, causes of hospitalization, and survival outcomes were recorded at the time of SLE diagnosis and during a follow-up period. Poisson regression models were created to identify the potential factors associated with frequency of hospitalization. RESULTS: Of 526 patients with SLE, 242 patients (46%) had 1 or more admissions amounting to a total of 449 times during a median follow-up period of 4.73 years. The annual hospitalization rate was 18% and death occurred in 2.5% of total admissions. SLE flare, infection and pregnancy-related morbidity were the most common causes of hospitalization. Besides, the multivariate Poisson regression analysis revealed that decreased albumin, decreased renal function, and high disease damage were the risk factors for more frequency of hospitalization, whereas positive anti-SSA antibody and use of hydroxychloroquine were protective factors. CONCLUSIONS: Nearly half of patients (46%) with SLE experience 1 or more hospitalizations, mainly due to SLE flare, infection, and pregnancy-related morbidity. Lupus patients with decreased albumin, decreased renal function, and high disease damage are more susceptible to have frequent hospitalization.