Evaluation of the ability of neurobiological, neurodevelopmental and socio-economic variables to predict cognitive outcome in premature infants

Background When developed in the 1990s, the Neurobiologic Risk Score (NBRS) and Neurodevelopmental Risk Exam (NRE) correlated well with developmental outcomes in premature infants. Given recent advances in neonatology, we assessed their present ability to predict cognitive outcome, alone and combined with socio-economic factors. Methods One hundred and twenty-nine neonates <32 weeks gestational age were assessed at 6, 12 and/or 24 months corrected age with the Cognitive Adaptive Test/Clinical Linguistic and Auditory Milestone Scale (CAT/CLAMS). Indices of socio-economic status included maternal education and marital status. Results At 24 months corrected age (n= 67), the NBRS (r=-0.5), maternal education (r= 0.46) and marital status (r= 0.37) correlated with the CAT/CLAMS. These correlations increased when NBRS and maternal education were combined (r= 0.63) and when specific NBRS components (intraventricular haemorrhage, periventricular leukomalacia, seizures) and maternal education were combined (r= 0.66). Conclusions In the contemporary neonatal intensive care unit, measures used to predict cognitive outcome should incorporate both neurobiological risk factors and socio-economic variables.