Worse global intellectual and worse neuropsychological functioning in preterm-born children at preschool age: a meta-analysis

Abstract

Aim: Preterm births (<32 weeks of gestational age) are associated with cognitive problems that are difficult to diagnose in infancy but potentially detectable at preschool age. This review aimed to evaluate the extent to which total intelligence quotient (IQ) and neuropsychological functions at ages three to five years differ between children born at <32 weeks gestational age or < 1500 g birth weight and children born at term. The secondary aim was to determine whether cognitive performance differs between extremely preterm (EPT)/extremely low birth weight (ELBW) children and very preterm (VPT) or very low birth weight (VLBW) children.

Methods: PubMed and PsycINFO databases were searched for cohort studies comparing IQ and neuropsychological functions in term-born and preterm-born children born after 1994.

Results: At ages three to five years, preterm-born children, compared with term-born ones, had worse IQ mean score (d = -0.77 [95% confidence interval -0.88 to -0.66]), attention, memory, visuomotor integration skill and executive functions. No differences were found between VPT/VLBW and EPT/ELBW children.

Conclusion: Preterm-born children showed poorer IQ and neuropsychological functions compared with term-born subjects already at preschool age. The extent of differences is similar to that detected at a later age.

Keywords: Extremely preterm children; Intelligence quotients; Neuropsychological deficits; Preschool age; Very preterm children.