ESPE Abstracts

Background: Birth weight (BW) is often used as a proxy for gestational age (GA) by studies on preterm birth. Recent data indicate that the terms very-low-birth-weight (VLBW; BW <1500 g) and very preterm (VP; GA <32 weeks) birth are not equivalent with regard to perinatal outcomes and postnatal growth up until final height. It is unknown whether the differences between these terms could be extended to long-term neurodevelopmental outcomes.

Objective and hypotheses: To compare neurodevelopmental outcomes at age 19 years between VP and VLBW infants.

Method: VP and/or VLBW subjects from the Project On Preterm and Small-for-gestational-age infants cohort were classified as i) VP+/VLBW+ (n=354), ii) VP+/VLBW- (n=144) or (3) VP-/VLBW+ (n=207), and compared with regard to: intelligence quotient (IQ) assessed with the Multicultural Capacity Test-Intermediate Level; neurological functioning using Touwen’s examination of mild neurologic dysfunction; hearing measured with audiometry; behavior assessed with the Young Adult Self Report (YASR) and the parent-reported Young Adult Behavior Checklist (YABCL); achieved education and occupation; and self-assessed health using the Health Utilities Index and the London Handicap Scale.

Results: At age 19 years, VP+/VLBW- infants exhibited a 3.5 (95% CI: 0.2–6.8) higher IQ score, a 1.5 (95% CI: 1.01–2.1) increased odds of higher education, 3.2 (95% CI: 1.1–5.3) dB better hearing, and lower scores on anxious behavior, attention problems and internalizing behavior as measured with both the YASR and YABCL compared to VP+/VLBW+ subjects, after adjusting for gender. Additionally, VP-/VLBW+ infants reported a 1.8 (95% CI: 1.2–2.6) increased odds of poor health compared to VP+/VLBW+ subjects.

Conclusion: At age 19 years, infants born VP+/VLBW+, VP+/VLBW- or VP-/VLBW+ have different neurodevelopmental outcomes, hence the terms VP and VLBW are not interchangeable. We recommend, at least for industrialized countries, to base inclusion for future studies in preterm populations on GA instead of BW.