Description
Fetal alcohol spectrum disorders (FASD) encompass the constellation of children affected by prenatal alcohol exposure, including fetal alcohol syndrome (FAS), which is diagnosed in the presence of central nervous system dysfunction, growth deficiency, and craniofacial abnormalities. The majority of alcohol-exposed children do not meet diagnostic criteria for FAS, but display similar behavioral and neurocognitive deficits. While previous studies have focused on comparisons to controls or other clinical groups, less attention has been paid to within-group heterogeneity. Heterogeneity may relate to the differential success of studies to accurately classify alcohol-exposed subjects and suggests that behavioral subtypes exist within this population. Evidence of subtypes may improve identification and the development of efficient interventions to alleviate risk for later negative life outcomes. The current study examined heterogeneity of behavior problems in FASD to identify subtypes within children with prenatal alcohol exposure. Subjects included children with heavy prenatal alcohol exposure (AE; n=136) and non-exposed, controls (CON; n=141) from a multisite study of FASD. Caregivers completed the CBCL. Executive functioning was evaluated using D-KEFS subtests. To determine behavioral profiles we conducted two latent profile analyses (LPA) using CBCL syndrome scales. The first LPA included AE and CON to verify behavioral deficits in the AE group. The second LPA included AE only to determine whether distinct behavioral profiles could be identified within FASD. For the second LPA, we tested executive functioning differences by comparing D-KEFS performance between subjects in resulting profiles using ANOVA techniques. It was hypothesized that (1) the first LPA would result in a 2-profile solution, (2) the second LPA would result in a 2-profile solution supporting the presence of behavioral subtypes of FASD, and (3) subtypes would differ on executive functioning abilities. The first LPA revealed a 3-profile solution best fit the discrimination of CON and AE. The second LPA revealed that AE alone was also best discriminated using a 3-profile solution. In both analyses, profiles were interpreted as average-, intermediate-, and clinicallevel profiles. In the first LPA, the average profile was entirely control subjects, the intermediate profile consisted mostly of AE subjects, and the clinical profile was entirely AE subjects, effectively confirming differences in behavior between the CON and AE groups. Examination of conditional response means from the second LPA showed that subjects in the clinical level profile reflected clinical-level externalizing behaviors and borderline clinicallevel internalizing behaviors. These subjects also demonstrated worse performance on Verbal Fluency Switching and Color-Word Interference Inhibition-Switching than those in the other two profiles, which did not differ. The current study confirmed behavior problems in FASD and demonstrated the heterogeneity of these problems within this population. Clinical implications include recognition that not all alcohol-exposed subjects are equally affected. As a result, response to behavioral interventions may vary. Findings also support reports of the relation between behavior and executive function and suggest that verbal fluency and cognitive flexibility may be effective targets for behavioral remediation. Knowledge of this heterogeneity will improve identification of children with prenatal alcohol exposure by underscoring the importance of using a multimodal assessment approach.
