title: Risk factors for mortality from acute lower respiratory infections (ALRI) in children under five years of age in low and middle-income countries: a systematic review and meta-analysis of observational studies.
abstract: OBJECTIVE
  To evaluate risk factors for death from acute lower respiratory infections (ALRI) in children in low- and middle-income countries.
  
  
  METHODS
  Systematic review and meta-analysis.
  
  
  METHODS
  Observational studies reporting on risk factors for death from ALRI in children below five years in low- and middle income countries.
  
  
  METHODS
  Medline, Embase, Global Health Library, Lilacs, and Web of Science to January 2014.
  Quality In Prognosis Studies tool with minor adaptations to assess the risk of bias; funnel plots and Egger's test to evaluate publication bias.
  
  
  RESULTS
  Out of 10,655 papers retrieved, 77 studies from 39 countries (198,359 children) met the inclusion criteria. Host and disease characteristics more strongly associated with ALRI mortality were: diagnosis of very severe pneumonia as per WHO definition (odds ratio 9.42, 95% confidence interval 6.37‒13.92); age below two months (5.22, 1.70‒16.03); diagnosis of Pneumocystis Carinii (4.79, 2.67‒8.61), chronic underlying diseases (4.76, 3.27‒6.93); HIV/AIDS (4.68, 3.72‒5.90); and severe malnutrition (OR 4.27, 3.47‒5.25). Socio-economic and environmental factors significantly associated with increased odds of death from ALRI were: young maternal age (1.84, 1.03‒3.31); low maternal education (1.43, 1.13‒1.82); low socio-economic status (1.62, 1.32‒2.00); second-hand smoke exposure (1.52, 1.20 to 1.93); indoor air pollution (3.02, 2.11‒4.31). Immunisation (0.46, 0.36‒0.58) and good antenatal practices (0.50, 0.31‒0.81) were associated with decreased odds of death.
  
  
  CONCLUSIONS
  Host and disease characteristics as well as socio-economic and environmental determinants affect the risk of death from ALRI in children. Together with the prevention and treatment of chronic diseases, interventions to modify underlying risk factors such as poverty, lack of female education, and poor environmental conditions, should be considered among the strategies to reduce ALRI mortality in children in low- and middle-income countries.
authors: WHO Collaborating Centre for Maternal and Child Health, Institute for Maternal and Child Health IRCCS Burlo Garofolo, Trieste, Italy; Department of Medicine, Surgery, and Health Science, University of Trieste, Trieste, Italy.
authors: Michela
authors: M
authors: Sonego
authors: Department of Medicine, Surgery, and Health Science, University of Trieste, Trieste, Italy.
authors: Maria Chiara
authors: MC
authors: Pellegrin
authors: WHO Collaborating Centre for Maternal and Child Health, Institute for Maternal and Child Health IRCCS Burlo Garofolo, Trieste, Italy.
authors: Genevieve
authors: G
authors: Becker
authors: WHO Collaborating Centre for Maternal and Child Health, Institute for Maternal and Child Health IRCCS Burlo Garofolo, Trieste, Italy.
authors: Marzia
authors: M
authors: Lazzerini
mesh_terms: D002675:Child, Preschool; D003906:Developing Countries; D004781:Environmental Exposure; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D064887:Observational Studies as Topic; D011203:Poverty; D012141:Respiratory Tract Infections / Q000401:mortality*; D012307:Risk Factors; D016019:Survival Analysis
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