Hospital experience and expected mortality in patients with systemic lupus erythematosus: a hospital level analysis

Objective. To determine whether a hospital's experience in treating patients with systemic lupus erythematosus (SLE) is associated with the risk of in-hospital mortality among these patients. Methods. The California Hospital Discharge Database, which contains information on all discharges from acute care hospitals in California, was used to identify patients with SLE hospitalized on an emergent or urgent basis from 1991 to 1994 (n = 9989). For each of the 413 hospitals at which these patients were hospitalized, expected mortality risks were computed based on a model that included patient demographic and clinical characteristics, and differences between the observed and expected numbers of deaths were calculated. This difference was then associated with the average annual number of patients with SLE admitted to each hospital on an emergent or urgent basis. Similar analyses were performed for the subset of 2372 patients hospitalized on an emergent basis (at 293 hospitals), and the subset of 405 patients hospitalized on an emergent basis due to SLE (at 122 hospitals). Results, In all 3 patient subsets, there was an inverse association between the average annual number of patients with SLE hospitalized on an urgent or emergent basis at a hospital and the difference between the observed and expected number of deaths at that hospital. Highly experienced hospitals had fewer than expected deaths, while there was little association between the difference between the observed and expected number of deaths among less experienced hospitals, Conclusion. Hospitals that treat larger numbers of patients with SLE have fewer than the expected number of deaths among such patients.