Relation over time between facial measurements and cognitive outcomes in fetal alcohol-exposed children

Abstract

Background: The identification of individuals exposed prenatally to alcohol can be challenging, with only those having the characteristic pattern of facial features, central nervous system abnormality, and growth retardation receiving a clinical diagnosis of fetal alcohol syndrome (FAS). Methods: Seventeen anthropometric measurements were obtained at 5 and 9 years from 125 Cape Town, South African children, studied since birth. The children were divided into 3 groups: FAS or partial FAS (PFAS), heavily exposed nonsyndromal (HE), and non-alcohol-exposed controls (C). Anthropometric measurements were evaluated for mean group differences. Logistic regression models were used to identify the subset of anthropometric measures that best predicted group membership. Anthropometric measurements were examined at the 2 ages in relation to prenatal alcohol exposure obtained prospectively from the mothers during pregnancy. Correlation of these facial measurements with key neurobehavioral outcomes including Wechsler Intelligence Scales for Children-IV IQ and eyeblink conditioning was used to assess their utility as indicators of alcohol-related central nervous system impairment. Results: Significant group differences were found for the majority of the anthropometric measures, with means of these measures smaller in the FAS/PFAS compared with HE or C. Upper facial widths, ear length, lower facial depth, and eye widths were consistent predictors distinguishing those exposed to alcohol from those who were not. Using longitudinal data, unique measures were identified that predicted facial anomalies at one age but not the other, suggesting the face changes as the individual matures. And 41% of the FAS/PFAS group met criteria for microtia at both ages. Three of the predictive anthropometric measures were negatively related to measures of prenatal alcohol consumption, and all were positively related to at least 1 neurobehavioral outcome. Conclusions: The analysis of longitudinal data identified a common set of predictors, as well as some that are unique at each age. Prenatal alcohol exposure appears to have its primary effect on brain growth, reflected by smaller forehead widths, and may suppress neural crest migration to the branchial arches, reflected by deficits in ear length and mandibular dimensions. These results may improve diagnostic resolution and enhance our understanding of the relation between the face and the neuropsychological deficits that occur.