Language Outcomes in Late Preterm Infants: A Population-based Birth Cohort Study
*Sheri Crow Department Of Pediatrics, Mayo Clinic, Rochester, MN, United States
*Corresponding Author: Sheri Crow
Department Of Pediatrics, Mayo Clinic, Rochester, MN, United States Email:Crow.firstname.lastname@example.org
Published on: 2018-12-03
Background: Growing evidence suggests late preterm birth (34 to 36 6/7 weeks gestational age) poses risk for neurodevelopmental deficit. Associations between late prematurity and language impairment (LI) are poorly understood. We hypothesized that late preterm infants are at higher risk for LI compared to term infants. Methods: Late preterm infants were matched 1:1 with term infants from a population based birth cohort. Matching criteria included gender, date of birth, maternal age and education level. Speech, language, and cognitive standardized test scores were abstracted from school and medical records. Operationalized research criteria were developed to define LI. Associations between infant and parental characteristics and LI incidence were evaluated with Cox proportional hazards models. Results: The population-based birth cohort included 11,136 infants born 1994-2000.Following exclusions, 717 matched pairs of late preterm and term infants were available for comparison. LI incidence was 2.8 times higher in the late preterm infants (hazard ratio 2.79, 95% CI 1.24-6.30, p=0.01). Lower maternal and paternal education levels (p<0.02) were positively correlated with LI incidence after late preterm birth. Among late preterm infants, 42% (n=300) required NICU admission. NICU admission was not associated with a higher incidence of LI (HR 1.29, 95% CI 0.55-3.04, p=0.56). Conclusions: Late preterm infants have a higher incidence of LI compared to term infants matched on gender, date of birth, maternal age and education level. These findings warrant close monitoring of language development in late preterm infants to optimize early detection and intervention for those with signs of delay.
Early preterm birth (<34 weeks gestational age [GA]) is a well-established risk factor for neurodevelopmental deficit, ranging from cerebral palsy to learning disabilities and speech and language impairment (LI). In general prevalence of language impairment is estimated to range from 2%-19%. Past investigations have documented higher rates of LI in children with early prematurity [1- 4]. Data suggests LI risk may be independent of perinatal and neonatal risk factors other than gestational age . The risks for neurodevelopmental deficit following late preterm birth (34 to <37 weeks GA) are not as well understood, and investigations to date have yielded mixed results [6-9].To our knowledge, only three investigations have evaluated outcomes related to language following late preterm birth. Although these investigations were based on small sample sizes with relatively short follow up duration, their findings suggest that late preterm birth is a risk factor for speech and language impairment (LI) [3,10,11]. Further investigation of LI risk after late preterm birth is needed to inform clinicians and families regarding follow-up and early intervention. Our objective was to identify and contrast LI in late preterm and term infants from a population-based birth cohort. We hypothesized that late preterm infants would have higher rates of LI at follow up than term infants matched on date of birth, gender, maternal age and education level.