ABSTRACT

Background: Children born preterm and/or small for gestational age (SGA) are at increased risk of poor cognitive outcomes, particularly in low and middle-income countries (LMICs).

Objectives: This study examined the cognitive and academic deficits during the school age years in children born preterm or SGA compared to term adequate for gestational age (AGA) in rural Vietnam.

Method: Children born to women in a preconception micronutrient supplementation trial in Vietnam were classified into three groups: preterm AGA (n =138), term SGA (n =169) and term AGA (n= 1134). Cognitive abilities were assessed using the Wechsler Intelligence Scale for Children, measuring four domains (verbal comprehension -VCI, perceptual reasoning -PRI, working memory -WMI, and processing speed Index scores - PSI) and full-scale intelligence quotient (FSIQ) at 6-7y and 10-11y. Academic achievement was assessed with math and language tests. ANOVA and multiple regression models were used to analyze differences in cognitive function and academic achievement at 6-7y and 10-11y by birth phenotypes.

Results: Compared to term AGA children, those born SGA had lower cognitive scores at both 6-7y (-2.3 VCI, -3.7 PRI, -2.1 PSI and -2.9 FSIQ) and 10-11y (-3.7 VCI, -3.5 PRI, -2.7 WMI, -1.9 PSI and -3.9 FSIQ). Children born SGA also had poorer academic achievement with lower language (5.3) and math (2.5) scores. Adjustments for maternal factors and home environment attenuated the associations, but the differences in VCI, PRI, FSIQ and language at 10-11y remained significant. There were no differences in cognitive function and academic achievement between children born preterm and AGA.

Conclusions: Our findings highlight the enduring association of birth phenotype on cognitive functioning and academic achievement during the school years, despite adjustments for maternal education and family environment. Further research is needed to implement effective interventions to improve birth outcomes and optimize child health and development in LMICs.