title: A systematic review of population-based studies of infective endocarditis.
abstract: BACKGROUND
  We sought to summarize and critically appraise the literature on the epidemiology of infective endocarditis (IE) in the general population.
  
  
  METHODS
  We retrieved population-based IE surveys by searching MEDLINE and EMBASE. Two reviewers independently extracted relevant data. We performed a metaregression to determine if temporal trends of IE characteristics exist.
  
  
  RESULTS
  Fifteen population-based investigations with 2,371 IE cases from seven countries (Denmark, France, Italy, the Netherlands, Sweden, United Kingdom, and United States) from 1969 to 2000 were eligible. Different case definitions and procedures were used to capture all IE cases, including census of existing diagnoses, record-linkage system, and direct contact survey. In the unadjusted regression, there was a decline in the proportion of IE patients with underlying rheumatic heart disease (RHD; 12%; 95% confidence interval [CI], - 21 to - 3%; p = 0.01) and an increase in the proportion of patients undergoing valve surgery (9%; 95% CI, 3 to 16%) per decade. After adjusting for country, the decline in IE cases with underlying RHD became nonsignificant, but the proportions of IE patients undergoing valve surgery increased 7% per decade (95% CI, - 4 to 14%; p = 0.06), and those with underlying prosthetic valve increased 7% per decade (95% CI, - 1 to 16%; p = 0.07). There were no significant temporal trends in the causative organisms.
  
  
  CONCLUSIONS
  Evidence from well-planned, representative IE epidemiologic surveys is scarce in many countries. Available studies suggest a changing distribution of underlying valvular heart disease in patients with IE and an increase in its surgical treatment.
authors.affiliation: Division of Infectious Diseases, Mayo Clinic College of Medicine, Mayo Clinic, Rochester, MN, USA. tleyjeh.imad@mayo.edu.
authors.forename: Imad M
authors.initials: IM
authors.lastname: Tleyjeh
authors.forename: Ahmed
authors.initials: A
authors.lastname: Abdel-Latif
authors.forename: Hazim
authors.initials: H
authors.lastname: Rahbi
authors.forename: Christopher G
authors.initials: CG
authors.lastname: Scott
authors.forename: Kent R
authors.initials: KR
authors.lastname: Bailey
authors.forename: James M
authors.initials: JM
authors.lastname: Steckelberg
authors.forename: Walter R
authors.initials: WR
authors.lastname: Wilson
authors.forename: Larry M
authors.initials: LM
authors.lastname: Baddour
mesh_terms: D004697:Endocarditis, Bacterial / Q000453:epidemiology*; D016021:Epidemiologic Studies; D005060:Europe / Q000453:epidemiology; D006306:Health Surveys; D006801:Humans; D015994:Incidence; D014481:United States / Q000453:epidemiology