Cognitive outcome varies in adolescents born preterm, depending on gestational age, intrauterine growth and neonatal complications

Abstract

AimThe aim of this study was to investigate long-term cognitive outcome in a cohort of 18-year-olds born preterm and previously assessed at the age of 5.5.MethodsWe tested 134 adolescents born preterm with a very low birthweight of <1500 g and 94 term-born controls with a comprehensive cognitive battery at 18 years of age. The cohort was subdivided into 73 extremely preterm, 42 very preterm and 19 moderately preterm infants with gestational ages of 23–27, 28–31 and 32–36 weeks, respectively. The moderately preterm group was dominated by adolescents born small for gestational age.ResultsVery preterm adolescents performed on a par with term-born controls. In contrast, extremely preterm adolescents displayed inferior results on all cognitive tests, more so if they had suffered neonatal complications. Moderately preterm adolescents scored lower than very preterm and full-term born adolescents, particularly on complex cognitive tasks.ConclusionAdolescents born at 28 weeks of gestation or later, with appropriate birthweight and no perinatal complications, functioned like term-born peers at 18 years of age. Extremely preterm birth per se posed a risk for long-term cognitive deficits, particularly executive deficits. Adolescents born moderately preterm but small for gestational age were at risk of general cognitive deficits.

Neurocognitive and Academic Outcomes at Age 10 Years of Extremely Preterm Newborns

“…1,2,6,18,33 Corresponding deficits among ELGAN participants across measures of attention, executive control, and processing speed as well as visual perception and fine motor control were also comparable to those reported for earlier cohorts. 4,6,14,34 Our findings indicate that schoolaged children born extremely preterm continue to be at significant risk of a wide range of neurocognitive and academic deficits.…”

“…Extremely preterm children are at heightened risk of deficits in IQ, [1][2][3][4][5][6] attention, 7,8 executive function, 4,6,[9][10][11][12][13][14] processing speed, [15][16][17] visual perception, 6,14 and visual-motor function. 6,14 Neurocognitive deficits are accompanied by delays in academic attainment.…”

“…1,21 However, effects of prematurity on neurocognitive outcomes have not been found consistently, 22 possibly because of small samples with restricted ranges of GA 22 and inadequate adjustment for confounding factors, such as intrauterine growth restriction. 4,23 Knowing whether lower GA places extremely preterm children at heightened risk of enduring neurocognitive impairment has important implications regarding the need to prioritize development of novel preventive and therapeutic strategies that minimize the impact of extreme immaturity. 24 We assessed neurocognitive and academic ability in a US cohort of 889 children aged 10 years who were born at 23 to 27 weeks' GA from 2002 to 2004.…”

A longitudinal model of executive function development from birth through adolescence in children born very or extremely preterm

“…Participant characteristics are displayed in Table 1. The cohort, attrition analyses, and assessments have been presented in greater depth in previous articles (Böhm, Katz-Salamon, Smedler, Lagercrantz, & Forssberg, 2002;Lundequist et al, 2015).…”

“…Comprehensive neuropsychological assessments were conducted at age 5.5 and 18 years. From this cohort, we have previously reported that executive function was a specific weakness at 5.5 years and remained so still at 18 years (Böhm, Smedler, & Forssberg, 2004;Lundequist et al, 2015). We now seek to further investigate executive function development in this cohort, leaning on Miyake and Friedman's theoretical model (2012) and the empirical support lent to it by Huizinga and colleagues (2006).…”