title: Frequency and determinants of vitamin A deficiency in children under 5 years of age with pneumonia.
abstract: BACKGROUND
  Vitamin A deficiency (VAD) has been closely related to acute respiratory infections (ARI), although information is still incomplete; for example, the frequency of VAD in children <5 years of age with pneumonia is not known, and the conditions associated with VAD have not been identified. This study was conducted to gain insight into the status of vitamin A in children with pneumonia. A secondary objective was to identify the sociodemographic, individual, and nutritional factors associated with VAD in these children.
  
  
  METHODS
  A cross-sectional study was conducted in the Mexican state of Hidalgo, one of the poorest in the country. Children with community-acquired pneumonia treated at nine public hospitals were included. Information was obtained by interviewing mothers, and ascertainment of vitamin A status was performed with relative-dose-response (RDR) test.
  
  
  RESULTS
  A total of 422 cases were included. VAD was identified in 17.8% of children; 50.3% showed normal results, 24.6% had liver reserve depletion, and 7.3% showed results attributable to the infectious process. Variables associated with VAD were as follows: age <2 months (OR 3.44, 95% CI: 1.84-9.24); children >6 months of age fed with formula (OR 0.37, 95% CI: 0.15-0.91), and affiliation with the Mexican Social Security Institute (IMSS) health system (OR 0.40, 95% CI: 0.22-0.72).
  
  
  CONCLUSIONS
  The frequency of VAD in children with community-acquired pneumonia confirms that the problem of deficiency persists in Mexico. The associated factors for VAD found in this study can be taken into account when planning and evaluating vitamin A supplementation activities in populations with high risk for deficiency.
authors.affiliation: Unidad de Investigación Médica en Oncología, Hospital de Oncología, Centro Médico Nacional Siglo XXI (CMN-SXXI), Instituto Mexicano del Seguro Social (IMSS), Av. Cuauhtemoc 330, Col. Doctores, 06720 México City, D.F., México. reymh@webtelmex.net.mx
authors.forename: Hortensia
authors.initials: H
authors.lastname: Reyes
authors.forename: Salvador
authors.initials: S
authors.lastname: Villalpando
authors.forename: Ricardo
authors.initials: R
authors.lastname: Pérez-Cuevas
authors.forename: Leticia
authors.initials: L
authors.lastname: Rodríguez
authors.forename: Miriam
authors.initials: M
authors.lastname: Pérez-Cuevas
authors.forename: Irene
authors.initials: I
authors.lastname: Montalvo
authors.forename: Héctor
authors.initials: H
authors.lastname: Guiscafré
mesh_terms: D002675:Child, Preschool; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D008099:Liver / Q000378:metabolism; D008297:Male; D008800:Mexico; D011014:Pneumonia / Q000150:complications*; D014801:Vitamin A / Q000008:administration & dosage / Q000097:blood; D014802:Vitamin A Deficiency / Q000150:complications / Q000453:epidemiology*
chemical_list: D014801:Vitamin A