LETTER: Epidemiology of Infective Endocarditis

Abstract

Little is known about the incidence and clinical outcomes of infective endocarditis (IE) involving native valves in Asian countries. This nationwide study investigated epidemiologic features and in-hospital mortality associated with IE in adults (age ≥18 years) based on Taiwan’s National Health Insurance database from 1997 through 2002. Of 7,240 enrolled patients with IE involving native valves, the mean age was 53 ± 19 years and 70% were men. The mean annual crude incidence was 7.6 per 100,000 inhabitants. The incidence was significantly higher in men than in women (10.4 vs 4.6 per 100,000; p <0.001). The incidence of IE increased steadily with age, ranging from 3.8 per 100,000 persons in patients <30 years of age to 33 per 100,000 persons in patients ≥80 years of age (p <0.001). Staphylococcal (32%) and streptococcal species (61%) were the most common causative pathogens. The mean in-hospital mortality rate was 18%. Multivariate analysis showed that male gender, older age (≥50 years), diabetes mellitus, heart failure, neurologic complications, renal insufficiency, respiratory failure, shock, and Staphylococcus species as the causative microorganism were independent predictors of in-hospital mortality. In conclusion, this Taiwanese study revealed a high incidence of IE in men and elderly subjects. The in-hospital mortality rate remained high. Patients with IE who also developed shock and respiratory failure were the most likely to have a poor outcome.