title: Environmental tobacco smoke exposure as a risk factor for infections in infancy.
abstract: OBJECTIVE
  This prospective observational study investigated the effect of environmental tobacco smoke (ETS) on frequency and severity of common infantile infections.
  
  
  METHODS
  In a representative sample of 926 infants, parental smoking was recorded at months 1 and 9 postpartum, and all infantile infectious episodes were recorded at 1, 3, 6, 9 and 12 months postpartum.
  
  
  RESULTS
  Both parents were regular smokers all through the first year in 107 (11.6%), at least one smoked regularly or occasionally in 492 (53.1%), and parents did not smoke at all in 327 (35.3%) families. Among mothers, 168 (18.1%) smoked perinatally. Infantile ETS exposure was associated with increased frequency of total infectious episodes (p = 0.025) and hospitalizations for infection (p = 0.007). In ETS exposed infants, birth in autumn and presence of siblings contributed to increased frequency of most infections and of hospital admissions for infection. By contrast, exclusive breastfeeding protected against the effect of ETS on total infantile infections (OR 0.982, 95% CI 0.965-0.999; p = 0.036), hospital admissions for infection (OR 0.980, 95% CI 0.961-0.999; p = 0.036) and thrush (OR 0.973, 95% CI 0.951-0.996; p = 0.022).
  
  
  CONCLUSIONS
  Our findings point to harmful effect of ETS on infantile health and further suggest that this effect may be enhanced or diminished by other factors. ETS should be regarded as a preventable risk factor for infections in infancy.
authors.affiliation: Department of Paediatrics, University of Crete, Crete, Greece.
authors.forename: F
authors.initials: F
authors.lastname: Ladomenou
authors.forename: A
authors.initials: A
authors.lastname: Kafatos
authors.forename: E
authors.initials: E
authors.lastname: Galanakis
mesh_terms: D001942:Breast Feeding; D016009:Chi-Square Distribution; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D007223:Infant; D007239:Infections / Q000209:etiology*; D019570:Inhalation Exposure / Q000009:adverse effects; D007407:Interviews as Topic; D008297:Male; D010343:Patient Admission / Q000706:statistics & numerical data; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011446:Prospective Studies; D012044:Regression Analysis; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D014028:Tobacco Smoke Pollution / Q000009:adverse effects*
chemical_list: D014028:Tobacco Smoke Pollution