title: Longitudinal lung function growth of Mexican children compared with international studies.
abstract: BACKGROUND
  Our aim was to compare the longitudinal lung function growth of Mexican children and adolescents with the collated spirometric reference proposed for international use and with that of Mexican-Americans from the National Health State Examination Survey III (NHANES) III study.
  
  
  METHODS
  A cohort of Mexican children in third year of primary school was followed with spirometry twice a year through secondary school. Multilevel mixed-effects lineal models separated by gender were fit for the spirometric variables of 2,641 respiratory-healthy Mexican children expressed as Z-scores of tested reference equations. Impact of adjustment by sitting height on differences with Mexican-American children was observed in a subsample of 1,987 children.
  
  
  RESULTS
  At same gender, age, and height, Mexican children had increasingly higher forced expiratory volume in 1 s (FEV1) and Forced vital capacity (FVC) than the children from the collated reference study (mean Z-score, 0.68 for FEV1 and 0.51 for FVC) and than Mexican-American children (Z-score, 0.23 for FEV1 and 0.21 for FVC) respectively. Differences with Mexican-Americans were not reduced by adjusting by sitting height.
  
  
  CONCLUSIONS
  For reasons that remain unclear, the gender-, age-, and height-adjusted lung function of children from Mexico City is higher than that reported by several international studies.
authors.affiliation: National Institute of Respiratory Diseases (INER), Mexico City, Mexico.
authors.forename: David
authors.initials: D
authors.lastname: Martínez-Briseño
authors.forename: Rosario
authors.initials: R
authors.lastname: Fernández-Plata
authors.forename: Laura
authors.initials: L
authors.lastname: Gochicoa-Rangel
authors.forename: Luis
authors.initials: L
authors.lastname: Torre-Bouscoulet
authors.forename: Rosalba
authors.initials: R
authors.lastname: Rojas-Martínez
authors.forename: Laura
authors.initials: L
authors.lastname: Mendoza
authors.forename: Cecilia
authors.initials: C
authors.lastname: García-Sancho
authors.forename: Rogelio
authors.initials: R
authors.lastname: Pérez-Padilla
mesh_terms: D000293:Adolescent; D002648:Child; D015331:Cohort Studies; D005260:Female; D006801:Humans; D038622:Internationality; D008137:Longitudinal Studies; D008297:Male; D008800:Mexico; D010366:Peak Expiratory Flow Rate; D012044:Regression Analysis; D012129:Respiratory Function Tests / Q000706:statistics & numerical data*; D013147:Spirometry