Epidemiological and mortality trends in infective endocarditis, a 17-year population-based prospective study.
BACKGROUND
The population at risk, the clinical and microbiological features of infective endocarditis (IE) have changed. Aim of our study was to evaluate the contemporary epidemiological trends, over a 17-year period in a definite region of Tuscany, Italy, to analyze the clinical outcomes and associated prognostic factors.


METHODS
From 1 January 1998 to 31 December 2014, all patients with a definite diagnosis of IE were prospectively entered in a data-base. The Health-Care system data-base was interrogated to capture patients who could have been missed. The final dataset derived by the merging of the two data-bases.


RESULTS
Incidence rate of IE was 4.6/100,000/y with a significant linear incidence increase. In hospitalized patients the incidence was 1.27/1,000 admissions. Over age 65 incidence rate was 11.7/100,000/y. Male/female ratio was 1.54:1. A temporal trend towards an increase in the mean population age was found (P=0.033). There was an increase in the incidence of Health-care associated IE, P=0.016. The most common microorganisms were staphylococcus aureus (25%) and coagulase-negative staphylococci (22%). In-hospital mortality was 24%. A trend towards an increase in mortality rate was found (P=0.055). Independent predictors of mortality were older age, S. aureus infection, heart failure, septic shock and persistent bacteremia.


CONCLUSIONS
Our study confirms an increasing mortality trend in IE, although with a borderline significance. Elderly forms are associated with poor prognosis and higher than 1-year mortality rate even in the multivariate analysis. Ageing population, increase in healthcare-associated and staphylococcal infections, may explain the rise of IE incidence and of the mortality trend.
Cardiological Department, Misericordia Hospital, Grosseto, Italy.
Alberto
A
Cresti
Division of Cardiothoracic Surgery, Department of Surgery, Le Scotte Hospital, Siena University, Siena, Italy.
Mario
M
Chiavarelli
Department of Epidemiology and Health Research, Institute of Clinical Physiology, National Council of Research, F. G. Monasterio, Pisa, Italy.
Marco
M
Scalese
Infectious Disease Department Misericordia Hospital, Grosseto, Italy.
Cesira
C
Nencioni
Infectious Disease Department Misericordia Hospital, Grosseto, Italy.
Silvia
S
Valentini
Cardiological Department, Misericordia Hospital, Grosseto, Italy.
Francesco
F
Guerrini
Cardiological Department, Misericordia Hospital, Grosseto, Italy.
Incoronata
I
D'Aiello
Cardiological Department, Misericordia Hospital, Grosseto, Italy.
Andrea
A
Picchi
Cardiological Department, Misericordia Hospital, Grosseto, Italy.
Francesco
F
De Sensi
Cardiology Department, Hôpital La Timone, Marseille, France.
Gilbert
G
Habib
Infective endocarditis (IE); community-acquired endocarditis; epidemiology; health-care associated endocarditis; temporal trends