Long‐term cognitive outcomes of infants born moderately and late preterm

Abstract

ABBREVIATION ALSPAC Avon Longitudinal Study of Parents and ChildrenAIM To investigate whether infants born late preterm have poorer cognitive outcomes than termborn infants.METHOD A cohort study based on the Avon Longitudinal Study of Parents and Children. Cognitive measures were assessed between the ages of 8 and 11 years. Exposure groups were defined as moderate ⁄ late preterm (32-36 weeks' gestation) or term (37-42wk). Regression models were used to investigate the association between gestational age and IQ.RESULTS Seven hundred and forty-one infants (5.4% of total eligible population; 422 males, 319females; mean (SD) birthweight 2495g [489]) were born between 32 and 36 weeks' gestation. The analysis was based on 6957 infants with IQ data at age 11 (50% of eligible infants). In the adjusted model, children born moderately and late preterm had similar IQ scores to peers born at term (mean difference [95% confidence interval] )0.18 [)1.88 to 1.52]). However, the preterm infants had a higher risk of having special educational needs at school (odds ratio 1.56 [1.18-2.07]).INTERPRETATION Despite an increased risk of special educational needs, there is little evidence of a reduction in IQ, memory, or attention measures at school age in children born between 32 and 36 weeks' gestation. Although interpretation is limited by the amount of missing data, further work is needed to identify why these infants have increased educational needs.The long-term effects of preterm birth are well documented in infants born before 32 weeks' corrected gestation. 1 Extreme preterm birth is associated with increased risks of cerebral palsy, 2 impairments in executive functioning, 3 as well as reduction in more global measures of cognition, 1 resulting in poorer educational achievement. 4 However, the long-term outcome of infants born only moderately preterm is less clear. Previous studies have suggested increased rates of educational difficulties in infants born before 37 weeks' gestation [5][6][7] and there is some evidence that measures of cognition may also be worse 8 . At present these infants receive little specific educational input or formal neurodevelopmental follow-up, unlike infants born at earlier gestations, and represent a much larger population than those born at earlier gestations.5 Recently the definitions of moderate (32-33 weeks' gestation) and late (34-36wk) preterm birth have been used to identify this group of infants.The aim of the present study was to investigate whether infants born at moderate and late preterm gestations (32-36wk) have poorer cognitive, memory, attention, or school outcomes in childhood than those born at term. METHODThis study is based on the Avon Longitudinal Study of Parents and Children (ALSPAC), an ongoing longitudinal study containing data on over 14 000 infants. 9 The cohort includes children born in the Bristol area of the UK, from April 1991 to December 1992. Further information about the study can be found on the ALSPAC website (http://www.alspac.bristol. ac.uk).Data on gestational a...

Bilingualism as a Potential Strategy to Improve Executive Function in Preterm Infants: A Review

“…In infancy, attention was assessed through measuring look duration and shift rate (Rose, Feldman, & Jankowski, 2009;Rose, Feldman, Jankowski, & Van Rossem, 2008). For children older than 3 years and adolescents, attention was most commonly assessed through tasks, such as the Attention Sustained Test, Test of Everyday Attention, and Continuous Performance Tasks, which require individuals to find targets in a display of nontargets as quickly as possible (selective attention) or to work on a task for an extended period (sustained attention; Bayless & Stevenson, 2007;Caravale et al, 2005Caravale et al, , 2012Cserjesi et al, 2012;Mulder, Pitchford, Hager, & Marlow, 2009;Mulder, Pitchford, & Marlow, 2011;Odd et al, 2012). Preterm-born children consistently show poorer selective attention and sustained attention across all gestational ages (Bayless & Stevenson, 2007;Caravale et al, 2005Caravale et al, , 2012Cserjesi et al, 2012;Hallin, Hellstrom-Westas, & Stjernqvist, 2010;Mulder et al, 2009;Nosarti et al, 2007;Rose et al, 2008Rose et al, , 2009Shum, Neulinger, O'Callaghan, & Mohay, 2008;Woodward, Clark, Pritchard, Anderson, & Inder, 2011).…”

“…Preterm-born children appeared to experience greater difficulty in identifying stimuli and using a search strategy, and were therefore less able to stay focused on one task (Woodward et al, 2011). However, some studies did not find a significant difference in attention (Mulder et al, 2011;Odd et al, 2012). No statistical difference in performance in attention was found in very preterm-born children at the age of 9 to 10 years (Mulder et al, 2011).…”

“…Neuropsychological testing reveals that persons born preterm perform more poorly on measures of executive function than do those born at term (Aarnoudse-Moens, Smidts, Oosterlaan, Duivenvoorden, & Weisglas-Kuperus, 2009; Baron, Kerns, Muller, Ahronovich, & Litman, 2012;Caravale, Mirante, Vagnoni, & Vicari, 2012;Cserjesi et al, 2012;Edgin et al, 2008;Kerstjens et al, 2011;Nosarti et al, 2007;Odd, Emond, & Whitelaw, 2012). Executive functions refer to multiple cognitive processes that control thoughts and behaviors, including information processing, inhibitory control, memory, attention, cognitive flexibility, problem solving, and planning.…”

ADHD and Learning Disabilities in Former Late Preterm Infants: A Population-Based Birth Cohort

“…13 Despite this increased level of concern, recent studies have provided conflicting findings on the rates of neurodevelopmental, learning, and behavioral problems in former late preterm infants compared with former term infants. [17][18][19][20][21] However, these studies have been limited primarily by the use of clinicreferred samples. Given this limitation and the importance of determining whether children born late preterm require closer longitudinal developmental monitoring, our study was designed to test the hypothesis that former late preterm infants have increased rates of ADHD and LD compared with term infants using a population-based birth cohort.…”

Towards reducing variations in infant mortality and morbidity: a population-based approach

“…These associations are also borne out in other studies in which resuscitation at birth, sociodemographic factors and pre-eclampsia, in particular, have been independently associated with long-term outcomes in this population. 175,199,200 Not receiving any breast milk at discharge, either expressed or by breastfeeding, was associated with disability at 2 years. The impact of breastfeeding on infant development has been widely reported, although the mechanisms for this association remain unclear in both term-born and preterm infants.…”