The Evolving Nature of Infective Endocarditis in Spain

BACKGROUND: Little information exists regarding population-based epidemiological changes in infective endocarditis (IE) in Europe. OBJECTIVES: This study sought to analyze temporal trends in IE in Spain from 2003 to 2014. METHODS: This retrospective, population-based, temporal trend study analyzed the incidence, epidemiological and clinical characteristics, and outcome of all patients discharged from hospitals included in the Spanish National Health System with a diagnosis of IE, from January 2003 to December 2014. RESULTS: Overall, 16,867 episodes of IE were identified during the study period, 66.3% in men. The rate of IE significantly increased, from 2.72 in 2003 to 3.49 per 100,000 person-years in 2014, and this rise was higher among older adults. The most frequent microorganisms were staphylococci (28.7%), followed by streptococci (20.4%) and enterococci (13.1%). Twenty-three percent of patients underwent cardiac surgery. The in-hospital mortality rate was 20.4%. Throughout the study period, the proportion of patients with previously known heart valve disease and diabetes mellitus significantly increased, whereas the prevalence of intravenous drug use decreased. Regarding microorganisms, Staphylococcus aureus and streptococci slightly declined, whereas coagulase-negative staphylococci and enterococci consistently increased over the years. In-hospital complications and cardiac surgery rates significantly increased across the years. The risk-adjusted in-hospital mortality rate diminished (0.2% per year) during the study period. CONCLUSIONS: The incidence of IE episodes significantly increased over the decade of the study period, particularly among older adults. Relevant changes in clinical and microbiological profile included older patients with more comorbidity and a rise in enterococci and coagulase-negative staphylococcal infections. Adjusted mortality rates slightly declined over the study period.