title: Prenatal exposure to influenza epidemics and risk of mental retardation.
abstract: This study was undertaken to determine whether prenatal exposure to influenza epidemics increases the risk of mental handicap. The monthly birth frequencies of 827 first-admission individuals (mean age at admission 13 years) with a primary diagnosis of non-specific mental retardation, discharged from psychiatric hospitals in England and Wales, were examined in relation to the monthly death rates from influenza over the period 1953-1980. The relative risk of developing mental handicap when exposed to influenza epidemics during mid-gestation was assessed by a generalized linear model. Increased death rates from influenza, a measure of prevalence of the infection, were significantly associated with an increase in births of mentally handicapped individuals 6 months later. For every 1000 female deaths from influenza there was a 17% increase in births of mentally handicapped individuals 6 months later. Maternal exposure to influenza at approximately the third to fourth month of gestation may be risk factor for developing mental handicap.
authors.affiliation: Department of Psychological Medicine, Institute of Psychiatry, London, UK.
authors.forename: N
authors.initials: N
authors.lastname: Takei
authors.forename: G
authors.initials: G
authors.lastname: Murray
authors.forename: E
authors.initials: E
authors.lastname: O'Callaghan
authors.forename: P C
authors.initials: PC
authors.lastname: Sham
authors.forename: G
authors.initials: G
authors.lastname: Glover
authors.forename: R M
authors.initials: RM
authors.lastname: Murray
mesh_terms: D000328:Adult; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D015994:Incidence; D007251:Influenza, Human / Q000150:complications* / Q000453:epidemiology; D008607:Intellectual Disability / Q000209:etiology*; D008297:Male; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D012189:Retrospective Studies; D012621:Seasons; D012720:Severity of Illness Index; D006113:United Kingdom / Q000453:epidemiology