title: Early respiratory morbidity in a multicultural birth cohort: the Generation R Study.
abstract: Ethnic disparities in the prevalence of asthma symptoms in children have been described. We evaluated to what extent the association between ethnic background and respiratory symptoms during the first 2 years of life could be explained by the mediating effect of risk factors for respiratory morbidity. The Generation R Study is a multiethnic, population-based birth cohort study. Pre and postnatal risk factors for respiratory morbidity were prospectively assessed by questionnaires. Information about ethnicity was available for 5,684 infants. The associations between ethnic background and lower respiratory symptoms at 12 and 24 months were evaluated with log-binomial regression models. Relative risks and 95 % confidence intervals (RR [95 % CI]) were computed for Cape Verdean, Moroccan, Antillean, Surinamese and Turkish ethnicity with Dutch ethnicity as the reference category. We found an increased risk of lower respiratory symptoms at 24 months in Antillean infants (1.32 [95 % CI 1.12-1.57]) that was mediated by early postnatal exposures (pets keeping, siblings, breastfeeding, daycare attendance, smoke exposure). Turkish infants also had an increased risk of lower respiratory symptoms at 12 and 24 months (1.14 [95 % CI 1.02-1.27] and 1.21 [95 % CI 1.07-1.38], respectively), partly explained by previous morbidity (eczema, infections and upper respiratory symptoms). There were no differences for Cape Verdean, Moroccan or Surinamese, as compared to Dutch infants. Hence, ethnic background was associated with respiratory symptoms during the first 2 years of life and this association was largely explained by mediating effects of known pre and postnatal risk factors for respiratory morbidity.
authors.affiliation: The Generation R Study Group, Erasmus University Medical Centre, Sophia Children's Hospital, Rotterdam, The Netherlands.
authors.forename: Carmelo
authors.initials: C
authors.lastname: Gabriele
authors.forename: Lindsay M
authors.initials: LM
authors.lastname: Silva
authors.forename: Lidia R
authors.initials: LR
authors.lastname: Arends
authors.forename: Hein
authors.initials: H
authors.lastname: Raat
authors.forename: Henriëtte A
authors.initials: HA
authors.lastname: Moll
authors.forename: Albert
authors.initials: A
authors.lastname: Hofman
authors.forename: Vincent W
authors.initials: VW
authors.lastname: Jaddoe
authors.forename: Johan C
authors.initials: JC
authors.lastname: de Jongste
mesh_terms: D001249:Asthma / Q000208:ethnology; D001723:Birth Rate / Q000208:ethnology; D005006:Ethnicity / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D009426:Netherlands; D011446:Prospective Studies; D012120:Respiration Disorders / Q000208:ethnology*; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking; D012959:Socioeconomic Factors