Temporal trends in incidence, patient characteristics, microbiology and in-hospital mortality in patients with infective endocarditis: a contemporary analysis of 86,469 cases between 2007 and 2019.

Background: Infective endocarditis (IE) is characterized by high morbidity and mortality rates, despite recent improvements in diagnostics and treatment. We aimed to investigate incidence, clinical characteristics, and in-hospital mortality in a large-scale nationwide cohort.

Methods: Using data from the German Federal Bureau of Statistics, all IE cases in Germany between 2007 and 2019 were analyzed. Logistic regression models were fitted to assess associations between clinical factors and in-hospital mortality.

Results: In total, 86,469 patients were hospitalized with IE between 2007 and 2019. The mean age was 66.5 ± 14.7 years and 31.8% (n = 27,534/86,469) were female. Cardiovascular (CV) comorbidities were common. The incidence of IE in the German population increased from 6.3/100,000 to 10.2/100,000 between 2007 and 2019. Staphylococcus (n = 17,673/86,469; 20.4%) and streptococcus (n = 17,618/86,469; 20.4%) were the most common IE-causing bacteria. The prevalence of staphylococcus gradually increased over time, whereas blood culture-negative IE (BCNIE) cases decreased. In-hospital mortality in patients with IE was 14.9%. Compared to BCNIE, staphylococcus and Gram-negative pathogens were associated with higher in-hospital mortality. In multivariable analysis, factors associated with higher likelihood of in-hospital mortality were advanced age, female sex, CV comorbidities (e.g., heart failure, COPD, diabetes, stroke), need for dialysis or invasive ventilation, and sepsis.

Conclusions: In this contemporary cohort, incidence of IE increased over time and in-hospital mortality remained high (~ 15%). While staphylococcus and streptococcus were the predominant microorganisms, bacteremia with staphylococcus and Gram-negative pathogens were associated with higher likelihood of in-hospital mortality. Our results highlight the need for new preventive strategies and interventions in patients with IE.