Study characteristics
| Study | Country | Data source | Population | Population size | Cases of IE | Analysis | Date of guideline | IE incidence trends | Change in IE incidence after guideline change | Prescription and bacteriological data |
|---|---|---|---|---|---|---|---|---|---|---|
| 1. Thornhill et al16 | UK 2000–2008 | Secondary user Service | All cases of IE admitted to hospitals in England | 49 233 300 (2000) 51 809 700 (2010) | NA | Monthly trends in cases of IE and deaths in hospital | 2008 (NICE) | Increasing rate of IE between 2002 and 2008 Increasing rate persisted after 2008 | Increasing trajectory did not change | Reduction in antibiotic prescription after 2008. No change in upward trend of cases attributed to oral streptococcus |
| 2. Duval et al17 | France 1991, 1999, 2008 | Three 1-year surveys in three French regions | Age >20 | 11 million | 993 | Age-standardised and sex-standardised IE annual incidence trends | 2002 (France) | Small, non-significant decline in incidence in 2008 compared with earlier sampling periods | No increase in incidence rates | Prescription data unavailable No increase in incidence of streptococcal IE |
| 3. Bikdeli et al18 | US 1999–2010 | Medicare | Age >65 Medicare beneficiaries | NA | 262 658 | Adjusted rates of hospital admission and 30-day and 1-year mortality | 2007 (AHA) | Adjusted hospitalisation rate increased from 1999 to 2005 and then declined progressively to 2010 | No change in declining trajectory | Prescription and bacteriological data unavailable |
| 4. Pasquali et al19 | USA 2003–2010 | Pediatric Health Information Systems (PHIS) database | Age <18 from 37 PHIS -participating centres | >5 million | 1157 | The rate of change in the annual number of IE hospitalisations over time | 2007 (AHA) | Hospitalisations for IE declined progressively throughout study period | No change in declining trajectory | Prescription data unavailable Decrease over time in IE cases associated with a code for oral streptococci |
| 5. Dayer et al20 | UK 2004–2013 | Hospital discharge episode statistics | All patients in English hospitals with a discharge diagnosis of ‘acute or subacute IE’ | NA | 19 804 | Interrupted time series analysis, to investigate effect of antibiotic prophylaxis on the incidence of IE | 2008 (NICE) | A consistent upward trend in population-corrected incidence of IE, with small but significant increase after 2008 | Cases increased significantly above the projected historical trend | Reduction in antibiotic prescription after 2008. Bacteriological data unavailable |
| 6. DeSimone et al21 | USA 1999–2013 | Endocarditis Registry at Mayo Clinic and Rochester Epidemiology Project | Olmsted County adults (≥18 years) with definite or possible IE caused by streptococcal viridans | NA | 27 | Age-adjusted and sex-adjusted incidence rates standardised against the 2010 US white population | 2007 (AHA) | Incidence of IE trended downward during the study period | No change in declining trajectory | Prescription data unavailable Only 16% of cases caused by streptococcus |
| 7. Pant et al22 | USA 2000–2011 | The Nationwide Inpatient Sample database | All patients discharged with acute and subacute bacterial endocarditis | NA | 457 052 | Interrupted time series analysis of IE incidence rates | 2007 (AHA) | Steady increase in the incidence of IE hospitalisations from 2000 to 2011 | No significant change in upward trend | Prescription data unavailable Increase in streptococcal IE cases after 2007 |
AHA, American Heart Association; IE, infective endocarditis; NICE, National Institute for Health and Care Excellence.