title: Long term sequelae from childhood pneumonia; systematic review and meta-analysis.
abstract: BACKGROUND
  The risks of long term sequelae from childhood pneumonia have not been systematically assessed. The aims of this study were to: (i) estimate the risks of respiratory sequelae after pneumonia in children under five years; (ii) estimate the distribution of the different types of respiratory sequelae; and (iii) compare sequelae risk by hospitalisation status and pathogen.
  
  
  METHODS
  We systematically reviewed published papers from 1970 to 2011. Standard global burden of disease categories (restrictive lung disease, obstructive lung disease, bronchiectasis) were labelled as major sequelae. 'Minor' sequelae (chronic bronchitis, asthma, other abnormal pulmonary function, other respiratory disease), and multiple impairments were also included. Thirteen papers were selected for inclusion. Synthesis was by random effects meta-analysis and meta-regression.
  
  
  RESULTS
  Risk of at least one major sequelae was 5.5% (95% confidence interval [95% CI] 2.8-8.3%) in non hospitalised children and 13.6% [6.2-21.1%]) in hospitalised children. Adenovirus pneumonia was associated with the highest sequelae risk (54.8% [39.2-70.5%]) but children hospitalised with no pathogen isolated also had high risk (17.6% [10.9-24.3%]). The most common type of major sequela was restrictive lung disease (5.4% [2.5-10.2%]) . Potential confounders such as loss to follow up and median age at infection were not associated with sequelae risk in the final models.
  
  
  CONCLUSIONS
  All children with pneumonia diagnosed by a health professional should be considered at risk of long term sequelae. Evaluation of childhood pneumonia interventions should include potential impact on long term respiratory sequelae.
authors.affiliation: Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, United Kingdom. karen.edmond@lshtm.ac.uk
authors.forename: Karen
authors.initials: K
authors.lastname: Edmond
authors.forename: Susana
authors.initials: S
authors.lastname: Scott
authors.forename: Viola
authors.initials: V
authors.lastname: Korczak
authors.forename: Catherine
authors.initials: C
authors.lastname: Ward
authors.forename: Colin
authors.initials: C
authors.lastname: Sanderson
authors.forename: Evropi
authors.initials: E
authors.lastname: Theodoratou
authors.forename: Andrew
authors.initials: A
authors.lastname: Clark
authors.forename: Ulla
authors.initials: U
authors.lastname: Griffiths
authors.forename: Igor
authors.initials: I
authors.lastname: Rudan
authors.forename: Harry
authors.initials: H
authors.lastname: Campbell
mesh_terms: D001249:Asthma / Q000150:complications; D029481:Bronchitis, Chronic / Q000150:complications; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008171:Lung Diseases / Q000150:complications; D008297:Male; D011014:Pneumonia / Q000150:complications / Q000503:physiopathology* / Q000628:therapy; D012107:Research Design; D012306:Risk; D013997:Time Factors