Table 2

Study characteristics

StudyCountryData sourcePopulationPopulation sizeCases of IEAnalysisDate of guidelineIE incidence trendsChange in IE incidence after guideline changePrescription and bacteriological data
1. Thornhill et al16UK
Secondary user ServiceAll cases of IE admitted to hospitals in England49 233 300 (2000)
51 809 700 (2010)
NAMonthly trends in cases of IE and deaths in hospital2008 (NICE)Increasing rate of IE between 2002 and 2008
Increasing rate persisted after 2008
Increasing trajectory did not changeReduction in antibiotic prescription after 2008. No change in upward trend of cases attributed to oral streptococcus
2. Duval et al17France
1991, 1999, 2008
Three 1-year surveys in three French regionsAge >2011 million993Age-standardised and sex-standardised IE annual incidence trends2002 (France)Small, non-significant decline in incidence in 2008 compared with earlier sampling periodsNo increase in incidence ratesPrescription data unavailable
No increase in incidence of streptococcal IE
3. Bikdeli et al18US
MedicareAge >65
Medicare beneficiaries
NA262 658Adjusted rates of hospital admission and 30-day and 1-year mortality2007 (AHA)Adjusted hospitalisation rate increased from 1999 to 2005 and then declined progressively to 2010No change in declining trajectoryPrescription and bacteriological data unavailable
4. Pasquali et al19USA
Pediatric Health Information Systems (PHIS) databaseAge <18 from 37 PHIS -participating centres>5 million1157The rate of change in the annual number of IE hospitalisations over time2007 (AHA)Hospitalisations for IE declined progressively throughout study periodNo change in declining trajectoryPrescription data unavailable
Decrease over time in IE cases associated with a code for oral streptococci
5. Dayer et al20UK
Hospital discharge episode statisticsAll patients in English hospitals with a discharge diagnosis of ‘acute or subacute IE’NA19 804Interrupted time series analysis, to investigate effect of antibiotic prophylaxis on the incidence of IE2008 (NICE)A consistent upward trend in population-corrected incidence of IE, with small but significant increase after 2008Cases increased significantly above the projected historical trendReduction in antibiotic prescription after 2008. Bacteriological data unavailable
6. DeSimone et al21USA
Endocarditis Registry at Mayo Clinic and Rochester Epidemiology ProjectOlmsted County adults (≥18 years) with definite or possible IE caused by streptococcal viridansNA27Age-adjusted and sex-adjusted incidence rates standardised against the 2010 US white population2007 (AHA)Incidence of IE trended downward during the study periodNo change in declining trajectoryPrescription data unavailable
Only 16% of cases caused by streptococcus
7. Pant et al22USA
The Nationwide Inpatient Sample databaseAll patients discharged with acute and subacute bacterial endocarditisNA457 052Interrupted time series analysis of IE incidence rates2007 (AHA)Steady increase in the incidence of IE hospitalisations from 2000 to 2011No significant change in upward trendPrescription data unavailable
Increase in streptococcal IE cases after 2007
  • AHA, American Heart Association; IE, infective endocarditis; NICE, National Institute for Health and Care Excellence.