title: Effect of Passive Smoking on the Growth of Pulmonary Function and Respiratory Symptoms in Schoolchildren.
abstract: BACKGROUND
  Environmental tobacco smoke affects the current and future health of children.
  
  
  OBJECTIVE
  To determine whether schoolchildren aged 8-17 years old residing at an altitude of 2,240 m and exposed to tobacco smoke at home presented a reduction in the growth of pulmonary function and a greater problem of respiratory symptoms and infections compared with non-exposed children.
  
  
  METHODS
  We followed, with questionnaires and spirometry, 1,632 boys and 1,555 girls from Mexico City and its metropolitan area (the Metropolitan Study to Evaluate the Chronic Effects of Pollution in School-age Children [EMPECE]) every six months for six years. The impact of passive smoking was estimated by mixed-effects models and Generalized Linear and Latent Mixed Models (GLLAMM), stratifying by gender and adjusting for age, height, weight, and ozone levels.
  
  
  RESULTS
  Passive smoking (reported by one-half of participants) was associated with reduced spirometric lung function (log transformed or as Z-scores) and a higher frequency of self-reported respiratory symptoms and respiratory infections. Levels of forced expiratory volume in 1 second and forced vital capacity in individuals exposed to passive smoking were 6.8 and 14.1 ml, respectively, below those of non-exposed children, and these values decreased with increasing number of smokers at home and higher ozone levels.
  
  
  CONCLUSIONS
  Passive smoking in children is a significant risk factor for respiratory disease and reduced lung function growth, which are additive with levels of air pollution, asthma, and the presence of respiratory symptoms.
authors.affiliation: Epidemiology and Social Science in Health, Instituto Nacional de Enfermedades Respiratorias (INER), Mexico City, Mexico.
authors.forename: Rosario
authors.initials: R
authors.lastname: Fernández-Plata
authors.affiliation: Population Health Research Center, Instituto Nacional de Salud Pública (INSP), Mexico City, Mexico.
authors.forename: Rosalba
authors.initials: R
authors.lastname: Rojas-Martínez
authors.affiliation: Epidemiology and Social Science in Health, Instituto Nacional de Enfermedades Respiratorias (INER), Mexico City, Mexico.
authors.forename: David
authors.initials: D
authors.lastname: Martínez-Briseño
authors.affiliation: Epidemiology and Social Science in Health, Instituto Nacional de Enfermedades Respiratorias (INER), Mexico City, Mexico.
authors.forename: Cecilia
authors.initials: C
authors.lastname: García-Sancho
authors.affiliation: Epidemiology and Social Science in Health, Instituto Nacional de Enfermedades Respiratorias (INER), Mexico City, Mexico.
authors.forename: Rogelio
authors.initials: R
authors.lastname: Pérez-Padilla
mesh_terms: D000293:Adolescent; D002648:Child; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008800:Mexico / Q000453:epidemiology; D015233:Models, Statistical; D012129:Respiratory Function Tests; D012140:Respiratory Tract Diseases / Q000453:epidemiology* / Q000209:etiology; D012141:Respiratory Tract Infections / Q000453:epidemiology* / Q000209:etiology; D012307:Risk Factors; D013147:Spirometry; D011795:Surveys and Questionnaires; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*; D014797:Vital Capacity
chemical_list: D014028:Tobacco Smoke Pollution