title: Sickle cell trait (HbAS) and stunting in children below two years of age in an area of high malaria transmission.
abstract: BACKGROUND
  While the protective effects of sickle cell trait (HbAS) against severe malaria and the resulting survival advantage are well known, the impact on the physical development in young children remains unclear. This study was aimed to investigate the relationship between HbS carriage and stunting in children below two years of age in a cohort from the Ashanti Region, Ghana.
  
  
  METHODS
  1,070 children were recruited at three months of age and followed-up for 21 months with anthropometric measurements performed every three months. Incidence rate ratios with 95% confidence intervals were calculated by Poisson regression to estimate the association of beta-globin genotypes with the number of malaria episodes. Odds ratios (OR) were calculated for the association between the occurrence of beta-globin genotypes and/or malaria episodes and stunting. The age-dependent between-group and within-group effects for the beta-globin genotypes were assessed by population-averaged models estimated by generalized estimation equation with autoregressive correlation structure.
  
  
  RESULTS
  Analyses showed a significantly lower age-dependent risk of stunting (OR 0.56; 95% CI 0.33-0.96) in carriers of the HbAS genotype (n = 102) in comparison to those with HbAA (n = 692). This effect was restricted to children who experienced malaria episodes during the observation period suggesting that the beneficial effect of the beta-globin HbS variant on the incidence of stunting is closely linked to its protection from mild malaria episodes.
  
  
  CONCLUSIONS
  The lower risk of chronic malnutrition in early childhood, mediated by protection against mild malaria episodes, may contribute to the survival advantage of HbAS carriers in areas of high malaria transmission.
authors.affiliation: University Medical Centre Hamburg-Eppendorf, Germany. kreuels@bni-hamburg.de
authors.forename: Benno
authors.initials: B
authors.lastname: Kreuels
authors.forename: Stephan
authors.initials: S
authors.lastname: Ehrhardt
authors.forename: Christina
authors.initials: C
authors.lastname: Kreuzberg
authors.forename: Samuel
authors.initials: S
authors.lastname: Adjei
authors.forename: Robin
authors.initials: R
authors.lastname: Kobbe
authors.forename: Gerd D
authors.initials: GD
authors.lastname: Burchard
authors.forename: Christa
authors.initials: C
authors.lastname: Ehmen
authors.forename: Matilda
authors.initials: M
authors.lastname: Ayim
authors.forename: Ohene
authors.initials: O
authors.lastname: Adjei
authors.forename: Jürgen
authors.initials: J
authors.lastname: May
mesh_terms: D000367:Age Factors; D002675:Child, Preschool; D015331:Cohort Studies; D016001:Confidence Intervals; D005500:Follow-Up Studies; D005838:Genotype; D005869:Ghana / Q000453:epidemiology; D006130:Growth Disorders / Q000150:complications* / Q000235:genetics; D006451:Hemoglobin, Sickle / Q000235:genetics; D006801:Humans; D015994:Incidence; D007223:Infant; D008288:Malaria / Q000150:complications / Q000453:epidemiology* / Q000235:genetics / Q000517:prevention & control; D008297:Male; D044342:Malnutrition; D016017:Odds Ratio; D015995:Prevalence; D012307:Risk Factors; D012805:Sickle Cell Trait / Q000097:blood / Q000150:complications / Q000453:epidemiology / Q000235:genetics*; D055544:beta-Globins / Q000235:genetics
chemical_list: D006451:Hemoglobin, Sickle; D055544:beta-Globins; C028671:hemoglobin AS