Neuronal biomarkers of cognitive development in preterm and term born infants: a multidimensional approach combining electrophysiology and peripheral blood biomarkers

Prematurity is a global health problem, affecting about 11% of infants born worldwide. Due to the recent advancements in neonatal medicine the rates of preterm births are increasing and especially the survival of very and extremely preterm. Preterm born infants are at high risk for neurodevelopmental deficits, which have a lifelong impact. Therefore it is of utmost clinical importance to find a screening tool to detect infants at high risk that can possibly benefit from early intervention programs.
In the present work we aim at investigating neuronal biomarkers in preterm and term born infants in order to examine their ability to predict neurodevelopmental outcome. Behavioral tests alone are inadequate to assess cognition in early infancy and therefore neuronal biomarkers are considered. Two methods are explored: an electrophysiological approach, using auditory event related potentials (AERPs) and a protein of neuroaxonal injury found in the blood named neurofilament (Nf). Three publications are included. First a systematic review of the literature, examining the association between AERPs and cognitive outcome in preterm born infants. This review is followed by a pilot study, where neonatal AERPs are investigated and correlated with neurodevelopmental outcome at 2 years in healthy very preterm and term born infants. In particular discrimination and habituation are examined as early forms of attention and learning respectively. Finally, we investigated a promising biomarker of neuroaxonal injury Nf light chain (NfL) for the very first time in preterm and term born infants during the first week of life.