The Relationship of Poor Linear Growth Velocity with Neonatal Illness and Two-Year Neurodevelopment in Preterm Infants

Background: Poor postnatal weight gain in very low birth weight (VLBW) preterm infants has been shown to have a negative effect on neurodevelopment. However, the dose-dependent neurodevelopmental consequences of linear stunting in this population have not previously been assessed. Understanding this relationship is important because organ growth and differentiation are more tightly linked to lean body mass and thus linear growth. Objective: To assess the duration and clinical determinants of poor linear growth and its relationship to neurodevelopment in preterm infants. Methods: Weight, recumbent length and head circumference were recorded at birth, hospital discharge, and at 4, 12 and 24 months corrected age (CA) in 62 VLBW infants. Standardized Z-scores for weight (WZ), length (LZ) and head circumference (HCZ) were calculated and assessed as a function of inpatient clinical factors using linear regression models. Twenty-four-month neurodevelopmental function was analyzed as a function of growth status. Results: Mean LZ was lower than WZ (p = 0.004) at hospital discharge, was related in part to illness severity and remained lower than baseline LZ until 24 months CA. Controlling for WZ and HCZ at each age, lower LZ at 4 and 12 months CA was associated with lower cognitive function scores at 24 months CA (p <= 0.03). Conclusions: Nutritional and non-nutritional factors influenced the degree of pre- and post-discharge linear growth suppression in VLBW infants, which in turn was negatively associated with developmental outcomes at 24 months CA. Since linear growth correlates with brain growth and indexes a number of clinical factors, it is an important biomarker that can be used in VLBW infants to predict long-term developmental outcomes. Copyright (C) 2012 S. Karger AG, Basel