Hospital experience and mortality in patients with systemic lupus erythematosus: which patients benefit most from treatment at highly experienced hospitals?

OBJECTIVE: To determine if hospitalization at a hospital experienced in the treatment of systemic lupus erythematosus (SLE), compared to hospitalization at a less experienced hospital, is associated with decreased in-hospital mortality in all subsets of patients with SLE, or if the decrease in mortality is greater for patients with particular demographic characteristics, manifestations of SLE, or reasons for hospitalization.
METHODS: Data on in-hospital mortality were available for 9989 patients with SLE hospitalized in acute care hospitals in California from 1991 to 1994. Differences in in-hospital mortality between patients hospitalized at highly experienced hospitals (those hospitals with more than 50 urgent or emergent hospitalizations of patients with SLE per year) and those hospitalized at less experienced hospitals were compared in patient subgroups defined by age, sex, ethnicity, type of medical insurance, the presence of common SLE manifestations, and each of the 10 most common principal reasons for hospitalization.
RESULTS: In univariate analyses, in-hospital mortality was lower among those hospitalized at a highly experienced hospital for women, blacks, and Hispanics, and those with public medical insurance or no insurance. The risk of in-hospital mortality was similar between highly experienced and less experienced hospitals for men, whites, and those with private insurance. Patients with nephritis also had lower risks of in-hospital mortality if they were hospitalized at highly experienced hospitals, but this risk did not differ in subgroups with other SLE manifestations or subgroups with different principal reasons for hospitalization. In multivariate analyses, only the interaction between medical insurance and hospitalization at a highly experienced hospital was significant. Results were similar in the subgroup of patients with an emergency hospitalization (n = 2,372), but more consistent benefits of hospitalization at a highly experienced hospital were found across subgroups of patients with an emergency hospitalization due to SLE (n = 405).
CONCLUSION: Risks of in-hospital mortality for patients with SLE were similar between highly experienced hospitals and less experienced hospitals for patients with private medical insurance, but patients without private insurance had much lower risks of mortality if hospitalized at highly experienced hospitals. The benefit of hospitalization at highly experienced hospitals was more consistent across subgroups of patients with a hospitalization due to SLE, suggesting that differences specifically in the treatment of SLE, rather than differences in the general quality of medical care, account for the lower mortality among patients with SLE hospitalized at highly experienced hospitals.