Prenatal, perinatal, and neonatal risk factors for speciﬁc language impairment: A prospec8ve cohort study (Whitehouse, Shelton, Ing, & Newnham, 2014)
KACIE WITTKE
NEURODEVELOPMENT
4/7/15
Mo8va8on
 SLI is one of the most common neurodevelopmental disorders  Long-‐term consequences to language impairment  Gene:c basis to language impairment v  But what are the pre-‐ and postnatal environmental factors involved in the expression of SLI? Previous research has been conducted retrospec:vely, mostly null ﬁndings v  Prospec:ve longitudinal study reduces demands on parent recall Par8cipants
 Western Australia Pregnancy Cohort (Raine Study): prospec:ve cohort inves:ga:on of pregnant women and their oﬀspring v  Final sample of 2,979 pregnancies (2,868 live-‐born children)  Inclusionary criteria for SLI-‐C and Comparison groups: v  SLI-‐C: combina:on of SLI-‐E + SLI-‐M (n = 26 children) ü  SLI-‐E: children assigned to SLI with expressive deﬁcits (n = 12) ü  SLI-‐M: children with mixed recep:ve and expressive disorder (n = 14) v  Comparison group: no signiﬁcant developmental delays (n = 1,799 children) Assessments
 Infant Monitoring Ques:onnaire (completed between at 12, 24, and 36 months)  Peabody-‐Picture Vocabulary Test-‐Revised (PPVT-‐R; completed at 5 and 10 years)  Clinical Evalua:on of Language Fundamentals, Third Edi:on (CELF-‐3; completed at 10 years)  Raven’s Colored Progressive Matrices (RCPM; completed at 10 years) Data on Risk Factors
 Prenatal (from concep/on prior to onset of labor) v  Mothers completed study ques:onnaires during the 18th and 34th weeks of pregnancy v  Researchers reviewed mother’s medical record for exis:ng and pregnancy-‐induced health complaints, complica:ons, and admiaance to hospital.  Perinatal (onset of labor to delivery of child) v  Labor characteris:cs were obtained from medical record (labor onset, fetal presenta:on on admiaance to hospital, maternal fever, administra:on of medica:ons during labor, dura:on of labor, atypical placental or umbilical cord shape, mode of delivery, birth order, and season of birth) v  Appropriateness of fetal growth, propor:on of op:mal birth weight (to classify IUGR)  Neonatal (end of delivery to discharge from hospital) v  Fetal health (:me to spontaneous respira:on, requirement of resuscita:on, evidence of birth trauma, Apgar scores, admiaance to intensive care) v  First few days of life (any complica:on such as poor sucking/feeding, hypoglycemia, jaundice, anemia, and diﬃculty maintaining temperature) Results: Socio-‐demographic Factors
Results: Language and Cogni7ve Abili7es
Results: Prenatal, Perinatal, and Neonatal Characteris7cs
Discussion
 No between-‐group diﬀerences on the majority of factors considered, including range of obstetric complica:on and labor/delivery characteris:cs.  Null ﬁndings replicate the other three exis:ng studies in this area, sugges:ng that the vast majority of prenatal, perinatal, and neonatal factors do not play a clear causal role in SLI. v  Tomblin et al. (1997): obtained obstetric history of children with SLI via phone interview, and found no group diﬀerences with TD peers in maternal exposure to disease and other teratogens during pregnancy, as well as a range of perinatal characteris:cs such as labor and mode of delivery v  Bishop (1997): compared obstetric records between a clinical group (84 twin pairs where one or both twins had SLI) with a control group
(36 twin pairs with no history of speech-‐language diﬃcul:es), and pre-‐eclampsia was the only factor more common in children with SLI v  Merricks et al. (2004): no associa:on between SLI and a range of obstetric complica:ons  Possibili*es: 1.  More subtle environmental eﬀects are involved in e:ology of SLI. 2.  Eﬀects of early life events on neurodevelopmental disorder are small and can be observed only when calcula:ng aggregate risk scores. Limita8ons
 Iden:ﬁca:on and characteriza:on of SLI group  Grouping SLI-‐E and SLI-‐M may have been too phenotypically heterogeneous.  Sample aari:on: 20% of original sample, and more common among children whose mothers did not complete secondary school educa:on.  Prevalence of SLI in current sample was 1.42%. References
 Bishop, D. V. M. (1997). Pre-‐ and perinatal hazards and family background in children with speciﬁc language impairments: A study of twins. Brain and Language, 56, 1-‐26.  Merricks, M., Stoa, C., Goodyer, I., & Bolton, P. (2004). The ae:ology of speciﬁc language impairment: No evidence of a role for obstetric complica:ons. Journal of Neural Transmission, 111, 773-‐789.  Tomblin, J. B., Smith, E., & Zhang, X. Y. (1997). Epidemiology of speciﬁc language impairment: Prenatal and perinatal risk factors. Journal of Communica*on Disorders, 30, 325-‐344.  Whitehouse, A. J. O., Shelton, W. M. R., Ing, C., & Newnham, J. P. (2014). Prenatal, perinatal, and
neonatal risk factors for speciﬁc language impairment: A prospec:ve pregnancy cohort study. Journal of Speech, Language, and Hearing Research, 57, 1418-‐1427.