Exploring the Existence of a Unique Neurodevelopmental Profile of Fetal Alcohol Spectrum Disorder

Abstract

There is a general lack of consensus in the diagnostic criteria of Fetal Alcohol Spectrum Disorder (FASD), which has ultimately resulted in the overlapping of the diagnostic criteria with those of other neurodevelopmental disorders. As a result, FASD is associated with multiple potentially comorbid neurodevelopmental disorders, namely externalizing disorders. However, the extent to which FASD co-occurs with such disorders is largely unknown. Furthermore, the lack of universally accepted diagnostic criteria, and the high rate of comorbidity make diagnosing FASD difficult. Accordingly, in an effort to improve the diagnosis of FASD, researchers have explored the existence of a neurodevelopmental profile of FASD – defined as the outward expression (behavioral and developmental) of the central nervous system damage caused by prenatal alcohol exposure – however, a neurodevelopmental profile unique to FASD remains to be identified. Therefore, the objective of the current thesis project was to i) determine to what extent neurodevelopmental disorders with prominent externalizing behaviors co-occur among children with FASD; and ii) determine if children with FASD exhibit a unique and discernible neurodevelopmental profile that will differentiate them from a) typically developing control children, and b) children with other neurodevelopmental disorders. The first objective was achieved by way of a comprehensive systematic literature search, followed by disorder-specific random-effects meta-analyses. The second objective was achieved by performing latent profile analyses on two samples – i) children with FASD and typically developing control children, and ii) children with FASD, children with other neurodevelopmental disorders and typically developing control children – using data on neurodevelopmental status and behavior. With respect to the prevalence of neurodevelopmental disorders with prominent externalizing behaviors among children with FASD, of the disorders investigated, Attention Deficit Hyperactivity Disorder was found to be the most common disorder, followed by Oppositional Defiant Disorder, Conduct Disorder and Autism Spectrum Disorder, in that order. In relation to the identification of a neurodevelopmental profile, the profile was successful in differentiating children with FASD from typically developing control children; however, it was unsuccessful in differentiating children with FASD from children with other neurodevelopmental disorders. These findings are reflective of the complexity of FASD and highlight the need for diagnostic refinement.