Risk factors of mid-term mortality of patients with infective endocarditis

In-hospital and long-term mortality of infective endocarditis (IE) are well noted, but the studies for mid-term (90-day) mortality of IE is still limited. We determine the mid-term mortality rate of IE and its significant predictors. Seventy patients with IE were hospitalised at St. Luke's International Hospital between January 1996 and March 2009, of whom 62 consecutive patients could be followed up for 90 days after diagnosis. We then calculated Kaplan-Meier (KM) estimates and performed time-to-event analysis. The mean (standard deviation, SD) age was 66.6 (15.3) years. Thirty-five patients (56%) were male. Blood cultures were positive in 87%. Causative microorganisms were: viridans group streptococci (23%), β-streptococci (16%), Staphylococcus aureus (15%), including methicillin-resistant S. aureus (MRSA) (5%). Thirty-three cases (53%) had at least one complication such as heart failure (34%), central nervous system (CNS) complication (29%) or emboli peripheral to CNS (6%). KM estimates (95% CI) of the 90-day mortality was 14.5% (7.8-25%). In multiple regression analysis using the Cox proportional hazards model, hazard ratios of at least one complication for the 90-day mortality was 8.2 (1.4-155). Mid-term mortality of IE continues to be high and the presence of at least one complication may be considered as an independent risk factor of mid-term mortality.