title: An association between high birth weight and schizophrenia in a Finnish schizophrenia family study sample.
abstract: Longitudinal cohort studies have implicated an association between both low and high birth weight and schizophrenia. It has been suggested that schizophrenia associated genes could augment an individual's susceptibility to adverse prenatal and perinatal environmental events. We investigated the association between birth weight and schizophrenia in a large Finnish schizophrenia family study sample. We utilized the birth weight data of 1051 offspring from 315 Finnish families with at least one offspring with a diagnosis of schizophrenia. We used a multivariate COX frailty model to analyze the effect of birth weight on the risk of developing schizophrenia within the families. Using information from the Medication Reimbursement Register and patient interviews, we further investigated the association of maternal type 2 diabetes and schizophrenia risk among offspring. High birth weight (>4000g) was associated with a 1.68-fold increase in schizophrenia susceptibility. Maternal diabetes at the time of data collection, a proxy for gestational diabetes, was associated with a 1.66-fold increase in the risk of developing schizophrenia among offspring. Our results corroborate recent findings showing an association between high birth weight and schizophrenia. Our results also point to a potential birth-weight independent association between maternal type 2 diabetes and schizophrenia among offspring.
authors.affiliation: National Institute for Health and Welfare, Department of Mental Health and Substance Abuse Services, Helsinki, Finland. asko.wegelius@hus.fi
authors.forename: Asko
authors.initials: A
authors.lastname: Wegelius
authors.forename: Annamari
authors.initials: A
authors.lastname: Tuulio-Henriksson
authors.forename: Maiju
authors.initials: M
authors.lastname: Pankakoski
authors.forename: Jari
authors.initials: J
authors.lastname: Haukka
authors.forename: Ulriika
authors.initials: U
authors.lastname: Lehto
authors.forename: Tiina
authors.initials: T
authors.lastname: Paunio
authors.forename: Jouko
authors.initials: J
authors.lastname: Lönnqvist
authors.forename: Jaana
authors.initials: J
authors.lastname: Suvisaari
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001724:Birth Weight / Q000235:genetics*; D005192:Family Health; D005260:Female; D005387:Finland / Q000453:epidemiology; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D016016:Proportional Hazards Models; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D012559:Schizophrenia / Q000453:epidemiology* / Q000235:genetics* / Q000401:mortality; D016019:Survival Analysis