The impact of hemodialysis on mortality risk and cause of death in Staphylococcus aureus endocarditis

Background: The risk of infective endocarditis (IE) is markedly increased in patients receiving chronic hemodialysis compared with the general population, but outcome data are sparse. The present study investigated causes and risk factors of mortality in a hemodialysis-treated end-stage kidney disease- (ESKD) and a non-ESKD population with staphylococcus (S.) aureus endocarditis. Methods: Hemodialysis-treated ESKD patients with S. aureus endocarditis were identified from Danish National Registries and Non-ESKD patients from The East Danish Database on Endocarditis. For establishing the cause of death The Danish Registry of Cause of Death was used. Independent risk factors of outcome were identified in multivariable Cox regression models. Results: One hundred twenty-one hemodialysis patients and 190 non-ESKD patients with S. aureus endocarditis were included during 1996-2012 and 2002-2012, respectively. The all-cause in-hospital mortality was 22.3% in hemodialysis- and 24.7% in non-ESKD patients. One-year mortality, excluding in-hospital mortality, was 26.4% in hemodialysis patients and 15.2% in non-ESKD patients. The hazard ratio of all-cause mortality in hemodialysis was 2.64 (95% CI 1.70-4.10) at > 70 days after admission compared with non-ESKD. Age (HR 1.03 (95% CI 1.02-1.04)) and diabetes mellitus (HR 2.17 (95% CI 1.54-3.10)) were independent risk factors of all-cause mortality. The hazard ratio of cardiovascular death in hemodialysis was 3.20 (95% CI 1.78-5.77) at > 81 days after admission compared with non-ESKD. Age and diabetes mellitus were independently related to cardiovascular death. Conclusion: All-cause in-hospital mortality rates were similar in hemodialysis and non-ESKD patients with S. aureus endocarditis whereas one-year mortality rates were significantly increased in the hemodialysis population.