Hospitalizations among Danish SLE patients: a prospective study on incidence, causes of admission and risk factors in a population-based cohort.

Objective To determine the incidence, duration and cause of hospitalization in a cohort of Danish patients with systemic lupus erythematosus (SLE). In addition, we investigated risk factors for admission and prolonged hospital stay. Methods A total of 155 SLE patients from a population-based cohort were included in the study during a period of 70 months, from January 2007 to October 2012. Data on frequency, cause and duration of hospitalizations were obtained by review of medical charts. Data on disease manifestations, organ damage and treatment were collected prospectively. Results A total of 101 of the 155 SLE patients (65%) had one or more hospitalization during the study period. The incidence rate of all hospitalizations was 0.50 per year. Leading causes of admission were complications to SLE or its treatment, but infections were also common. Mean duration of hospital stay was 6.4 ± 10.5 days, and SLE Disease Activity Index 2000 (SLEDAI-2K) on admission emerged as a risk factor for prolonged hospital stay. Conclusion Danish SLE patients experience frequent admissions to hospital. Complications to SLE or its treatment, as well as infections, are leading causes of admission. High SLEDAI-2K on admission is a risk factor for prolonged hospital stay.