title: Variations in prenatal sociodemographic factors associated with intellectual disability: a study of the 20-year interval between two birth cohorts in northern Finland.
abstract: The authors followed two cohorts of children born in northern Finland in 1966 (n = 12,058) and 1985-1986 (n = 9,432) to examine whether associations between maternal sociodemographic factors assessed during pregnancy and intellectual disability in the offspring changed over a 20-year interval. Both of the cohorts were followed up to the age of 11.5 years using similar methods and definitions of intellectual disability. Data on sociodemographic factors were based on comparable questionnaires returned by the mothers during the 25th week of gestation. Despite an interval of 20 years between the cohorts, the main indicators of socioeconomic disadvantage and maternal multiparity remained as having the largest impact on the incidence of intellectual disability, while single factors such as older maternal age at delivery, being single, and living in a remote area lost their association with intellectual disability. Over 20 years, prepregnancy maternal obesity (body mass index > or =30) became a newly associated factor (adjusted odds ratio = 2.8, 95% confidence interval: 1.5, 5.3). A future challenge is to explore the mediating mechanisms between intellectual disability and its associated preventable intergenerational environmental or lifestyle factors.
authors.affiliation: Department of Public Health Science and General Practice, Faculty of Medicine, University of Oulu, Oulu, Finland.
authors.forename: Ulla
authors.initials: U
authors.lastname: Heikura
authors.forename: Anja
authors.initials: A
authors.lastname: Taanila
authors.forename: Anna-Liisa
authors.initials: AL
authors.lastname: Hartikainen
authors.forename: Päivi
authors.initials: P
authors.lastname: Olsen
authors.forename: Sirkka-Liisa
authors.initials: SL
authors.lastname: Linna
authors.forename: Lennart
authors.initials: L
authors.lastname: von Wendt
authors.forename: Marjo-Riitta
authors.initials: MR
authors.lastname: Järvelin
mesh_terms: D017677:Age Distribution; D015331:Cohort Studies; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008607:Intellectual Disability / Q000453:epidemiology*; D008137:Longitudinal Studies; D008423:Maternal Age; D015999:Multivariate Analysis; D009765:Obesity / Q000453:epidemiology; D016017:Odds Ratio; D010298:Parity; D011247:Pregnancy; D011295:Prenatal Care / Q000706:statistics & numerical data; D049188:Prenatal Injuries / Q000453:epidemiology*; D012044:Regression Analysis; D012307:Risk Factors; D012959:Socioeconomic Factors