Linear Growth and Neurobehavioural Outcome in Preterm Neonates (<34 Weeks) at 37 Weeks and 40 Weeks of Corrected Gestational Age : a Prospective Observational Study

Growth of the preterm infant has historically been defined as weight gain over time. As weight gain and nutrition have been more extensively studied and their relationships with neurodevelopmental outcomes have been established, other growth parameters and their relationships to outcome need to be assessed.

Large multicenteric studies have demonstrated that poor postnatal weight gain has a negative effect on neurodevelopment . However, the neurodevelopmental consequences of linear stunting in this population were not assessed .Understanding this relationship is important because organ growth and differentiation are more closely linked to lean body mass and thus linear growth than to weight gain or fat mass alone. Moreover, weight gain and linear growth are not always tightly linked and may be influenced by both nutritional and non nutritional factors.

Linear growth represents lean body mass and protein accretion and also indexes organ growth and development, including the brain. American Academy of Pediatrics (AAP) recommends that preterm infants should grow similar to the fetus,but this guideline has been mostly applied to weight gain. As already described, the ideal weight gain to optimize neurodevelopmental outcomes has been studied extensively. However, ideal linear growth has yet to be defined. Intrauterine linear-growth velocity is approximately 1 cm/wk,and therefore is the goal that most neonatologists currently follow.Given the increasing evidence that linear-growth suppression is associated with poorer cognitive outcomes,length may now be an important anthropometric biomarker for later neurodevelopment. Research is needed to determine optimal goals of linear growth for preterm infants so as to optimize later growth and neurodevelopmental outcomes.

Recently the role of neurobehaviour has evaluated as early as at 37-40 weeks of CGA and is being predicted as an useful adjunct to the 12-18 month full neurodevelopmental assessment .Neurobehavioural assessment by tools like NAPI have been shown to correlate with BSID score at 18 months of corrected gestational age in preterm neonates.This has tremendous implications in terms of initiating an early rehabilitation /stimulation program for these neonates..

There is insufficient data on Correlation of linear growth and neurological outcome in preterm VLBW babies in India.With majority of VLBW neonates in India being SGA this assumes critical significance as growth faltering is reported to continue as late as 24 months postnatally.The linkage of linear growth faltering and poor neurodevelopmental outcome needs to be detected early in the India population and corrective strategies need to be instituted