title: Active surveillance for rheumatic heart disease in endemic regions: a systematic review and meta-analysis of prevalence among children and adolescents.
abstract: BACKGROUND
  Rheumatic heart disease accounts for up to 250 000 premature deaths every year worldwide and can be regarded as a physical manifestation of poverty and social inequality. We aimed to estimate the prevalence of rheumatic heart disease in endemic countries as assessed by different screening modalities and as a function of age.
  
  
  METHODS
  We searched Medline, Embase, the Latin American and Caribbean System on Health Sciences Information, African Journals Online, and the Cochrane Database of Systematic Reviews for population-based studies published between Jan 1, 1993, and June 30, 2014, that reported on prevalence of rheumatic heart disease among children and adolescents (≥ 5 years to <18 years). We assessed prevalence of clinically silent and clinically manifest rheumatic heart disease in random effects meta-analyses according to screening modality and geographical region. We assessed the association between social inequality and rheumatic heart disease with the Gini coefficient. We used Poisson regression to analyse the effect of age on prevalence of rheumatic heart disease and estimated the incidence of rheumatic heart disease from prevalence data.
  
  
  RESULTS
  We included 37 populations in the systematic review and meta-analysis. The pooled prevalence of rheumatic heart disease detected by cardiac auscultation was 2·9 per 1000 people (95% CI 1·7-5·0) and by echocardiography it was 12·9 per 1000 people (8·9-18·6), with substantial heterogeneity between individual reports for both screening modalities (I² = 99·0% and 94·9%, respectively). We noted an association between social inequality expressed by the Gini coefficient and prevalence of rheumatic heart disease (p = 0·0002). The prevalence of clinically silent rheumatic heart disease (21·1 per 1000 people, 95% CI 14·1-31·4) was about seven to eight times higher than that of clinically manifest disease (2·7 per 1000 people, 1·6-4·4). Prevalence progressively increased with advancing age, from 4·7 per 1000 people (95% CI 0·0-11·2) at age 5 years to 21·0 per 1000 people (6·8-35·1) at 16 years. The estimated incidence was 1·6 per 1000 people (0·8-2·3) and remained constant across age categories (range 2·5, 95% CI 1·3-3·7 in 5-year-old children to 1·7, 0·0-5·1 in 15-year-old adolescents). We noted no sex-related differences in prevalence (p = 0·829).
authors.affiliation: Institute of Social and Preventive Medicine and Clinical Trials Unit, University of Bern, Bern, Switzerland.
authors.forename: Martina
authors.initials: M
authors.lastname: Rothenbühler
authors.affiliation: Department of Cardiology, Bern University Hospital, Bern, Switzerland.
authors.forename: Crochan J
authors.initials: CJ
authors.lastname: O'Sullivan
authors.affiliation: Department of Cardiology, Bern University Hospital, Bern, Switzerland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Stortecky
authors.affiliation: Department of Cardiology, Bern University Hospital, Bern, Switzerland.
authors.forename: Giulio G
authors.initials: GG
authors.lastname: Stefanini
authors.affiliation: Department of Cardiology, Bern University Hospital, Bern, Switzerland.
authors.forename: Ernest
authors.initials: E
authors.lastname: Spitzer
authors.affiliation: Institute of Social and Preventive Medicine and Clinical Trials Unit, University of Bern, Bern, Switzerland.
authors.forename: Janne
authors.initials: J
authors.lastname: Estill
authors.affiliation: Department of Cardiology, BP Koirala Institute of Health, Dharan, Nepal.
authors.forename: Nikesh R
authors.initials: NR
authors.lastname: Shrestha
authors.affiliation: Institute of Social and Preventive Medicine and Clinical Trials Unit, University of Bern, Bern, Switzerland.
authors.forename: Olivia
authors.initials: O
authors.lastname: Keiser
authors.affiliation: Institute of Social and Preventive Medicine and Clinical Trials Unit, University of Bern, Bern, Switzerland.
authors.forename: Peter
authors.initials: P
authors.lastname: Jüni
authors.affiliation: Department of Cardiology, Bern University Hospital, Bern, Switzerland. Electronic address: thomas.pilgrim@insel.ch.
authors.forename: Thomas
authors.initials: T
authors.lastname: Pilgrim
mesh_terms: D000293:Adolescent; D017677:Age Distribution; D002648:Child; D002675:Child, Preschool; D005260:Female; D054624:Health Status Disparities; D006801:Humans; D015994:Incidence; D007843:Latin America / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D012214:Rheumatic Heart Disease / Q000453:epidemiology*; D012959:Socioeconomic Factors