title: Prenatal exposure to cooking gas and respiratory health in infants is modified by tobacco smoke exposure and diet in the INMA birth cohort study.
abstract: BACKGROUND
  Studies that have evaluated the association between exposure to gas appliances emissions at home with respiratory health in children obtained heterogeneous and limited results. The aim of this study is to analyze the association between the use of gas cooking at home during pregnancy and respiratory problems in children during their first year of life.
  
  
  METHODS
  In the years 2003 through 2008 pregnant women were enrolled in 4 Spanish areas and visited in different age-points following a common protocol. Outcomes studied (from a questionnaire) were any episode of lower respiratory tract infection (LRTI), wheezing, persistent cough, chestiness and otitis. The association between exposure to gas cooking at home and respiratory outcomes was assessed using logistic regression and adjusting by confounding variables. Some potential effect modifiers (i.e. smoking, fruit and vegetables consumption) were examined.
  
  
  RESULTS
  Among the 2003 children included in the study, a total of 731 (36.6%) had a LRTI episode, 693 (34.6%) experienced wheezing, 302 (15.5%) a persistent cough, 939 (47.4%) chestiness and 620 (31.2%) had an episode of otitis during their first year of life. Gas cookers were present in 45.5% of homes. Exposure to gas cooking in homes was not associated with respiratory outcomes Odds Ratios (OR) were close to 1 and not statistically significant. However, a positive association was found for otitis among infants whose mothers reported low intakes of fruit and vegetables during pregnancy [OR (95% CI) = 1.38 (1.01-1.9)] and also wheezing and chestiness were associated with gas cookers among those children whose mothers smoked during pregnancy.
  
  
  CONCLUSIONS
  In susceptible subjects (those whose mothers smoke and consumed below average fruit and vegetables) we found an association between exposure to gas cooking during pregnancy and risk of wheezing, chestiness and otitis during the first year of life. But more research is needed regarding not only gas cooking and respiratory health but also the possible effect modifier role of diet and tobacco.
authors.affiliation: CIBER Epidemiología y Salud Pública (CIBERESP), Melchor Fernández Almagro, 3-5, 28029, Madrid, Spain. esplugues_ana@gva.es.
authors.forename: Ana
authors.initials: A
authors.lastname: Esplugues
authors.forename: Marisa
authors.initials: M
authors.lastname: Estarlich
authors.forename: Jordi
authors.initials: J
authors.lastname: Sunyer
authors.forename: Virginia
authors.initials: V
authors.lastname: Fuentes-Leonarte
authors.forename: Mikel
authors.initials: M
authors.lastname: Basterrechea
authors.forename: Martine
authors.initials: M
authors.lastname: Vrijheid
authors.forename: Isolina
authors.initials: I
authors.lastname: Riaño
authors.forename: Loreto
authors.initials: L
authors.lastname: Santa-Marina
authors.forename: Adonina
authors.initials: A
authors.lastname: Tardón
authors.forename: David
authors.initials: D
authors.lastname: Martinez
authors.forename: Ferran
authors.initials: F
authors.lastname: Ballester
mesh_terms: D000328:Adult; D000393:Air Pollutants / Q000633:toxicity*; D016902:Air Pollution, Indoor; D015331:Cohort Studies; D003296:Cooking; D004032:Diet; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D059206:Natural Gas / Q000633:toxicity*; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000453:epidemiology* / Q000209:etiology; D012140:Respiratory Tract Diseases / Q000453:epidemiology* / Q000209:etiology; D013030:Spain / Q000453:epidemiology; D011795:Surveys and Questionnaires; D014028:Tobacco Smoke Pollution / Q000009:adverse effects / Q000032:analysis; D055815:Young Adult
chemical_list: D000393:Air Pollutants; D059206:Natural Gas; D014028:Tobacco Smoke Pollution