Early-life growth of preterm infants and its impact on neurodevelopment.

Background: Increasing numbers of preterm-born children survive nowadays, and improving long-term health and neurodevelopment is becoming more important. Early-life growth has been linked to neurodevelopmental outcomes. We aimed to study whether this association has changed with time.

Methods: We studied two cohorts of preterm-born children (gestational age ≤32 weeks and/or birth weight ≤1500 g) from 1983 (n = 708) and 2003-2006 (n = 138), respectively. We distinguished four early-life growth patterns at 3 months corrected age: appropriate for gestational age (AGA) with or without growth restriction (AGA GR+/AGA GR-), and small for gestational age (SGA) with or without catch-up growth (SGA CUG+/SGA CUG-). Intelligence quotient (IQ), neuromotor function, and behavior were assessed at ages 19 and 8 years, respectively, for the cohorts.

Results: In the 2003-2006 cohort, less children had early-life GR. In both cohorts, SGA CUG- subjects had unfavorable growth trajectories and neurodevelopmental outcomes (IQ β -6.5, 95% confidence interval (CI) -9.8; -3.2, P < 0.001; neuromotor score β -1.9%, 95% CI -3.2; -0.6, P = 0.005), while SGA CUG+ subjects were comparable to adequately grown subjects.

Conclusion: Although the incidence of adverse growth patterns decreased between the cohorts, possibly indicating improvements in care over time, the impact of these growth patterns on neurodevelopmental outcomes was not significantly different. Achieving adequate early-life growth may be crucial for improving neurodevelopmental outcomes, especially for preterms born SGA.