Pathways of neuronal and cognitive development in children born small-for-gestational age or late preterm.

OBJECTIVE: To assess the effects of late small-for-gestational-age (SGA) birth and late prematurity on cognitive outcomes and structural changes in the central nervous system at primary school age, using a novel approach to examine changes in neuronal integrity of the retina. METHODS: We conducted a cross-sectional study of 347 children aged 6-13 years, including in the analysis only infants born after 34 weeks' gestation. We recorded all perinatal outcomes through a survey of parents. Neuronal damage was evaluated using optical coherence tomography of the retina. In a subgroup of 112 children aged 6-8 years, visuospatial perception was evaluated with the Children's Bender Visual Motor Gestalt Test. RESULTS: The proportions of SGA and late preterm children were 11.8 and 6.3%, respectively. Prematurity and SGA were simultaneously present in five children. When compared with controls, SGA children showed significantly lower than average retinal nerve fiber layer (RNFL) thickness (94.1 vs 98.8 µm; P = 0.007) and an increased percentage of abnormal Bender scores (27.3 vs 6.2%; P = 0.017) (odds ratio 5.6 (95% CI, 1.2-26.8)). These differences increased when late SGA infants with a birth weight below the 3(rd) percentile were compared with SGA infants with a birth weight between the 3(rd) and 10(th) percentiles and with controls, for RNFL thickness (92.5 vs 94.6 and 98.8 µm, respectively; P = 0.021) and abnormal Bender tests (33.3 vs 25.0 and 6.2%, respectively; P = 0.036). However, no differences were found in retinal structure and visuomotor performance between late preterm and term infants. CONCLUSIONS: These data suggest that late SGA and late prematurity induce a distinct neuronal pattern of structural changes that persist at school age. Late-onset SGA infants are at increased risk for axonal loss in the retina and present specific visuomotor difficulties.

Axonal loss and cognitive deficits in term infants with normal umbilical artery Doppler born small-for-gestational age.

OBJECTIVE: To assess cognitive outcomes and structural changes in the central nervous system, the latter using a novel approach to examine changes in neuronal integrity of the optic nerve, in children at 5-6½ years of age who were born small-for-gestational age (SGA) at term having shown normal umbilical artery (UA) Doppler. METHODS: We compared neuronal damage, cognitive deficits and visuospatial perception in two cohorts of infants, one born SGA (n = 40) and one born appropriate-for-gestational age (AGA) (n = 39) in weight. Neuronal damage was evaluated using optical coherence tomography (OCT) of the optic nerve. Cognitive deficits were assessed with the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) test. Visuospatial perception was evaluated with Rey-Osterreich Complex Figure (ROCF) tasks. RESULTS: Children from the SGA group had a significantly thinner average retinal nerve fiber layer (RNFL) compared with those from the AGA group (98.2 vs 104.5 µm, P = 0.012). Children from the SGA group exhibited impaired performance in copy tasks on the ROCF (3.27 vs 3.56, P = 0.036) and a higher rate of suboptimal WPPSI test performance intelligence quotient scores (15% vs 0%; P = 0.025) compared with those from the AGA group. CONCLUSION: Term infants with normal UA Doppler born SGA are at increased risk for cognitive deficits and axonal loss in the RNFL at the age of 5-6½ years.