Prenatal Alcohol Exposure is Associated with Impairments in Executive Function

M. O’Brien, P. K. Goh, S. N. Mattson, and the CIFASDCenter for Behavioral Teratology, San Diego State University

Research supported by NIAAA grant U01 AA014834

Executive function refers to a set of higher order processes including hierarchical thinking, organizational skills, and working memory.

Many children prenatally exposed to alcohol display impairments in executive function. These impairments differ from non-exposed children with attention-deficit/hyperactivity disorder (ADHD).

Using data from phase three of the Collaborative Initiative on Fetal Alcohol Spectrum Disorders (CIFASD III), we aimed to extend previous findings by comparing executive function ability between children prenatally exposed to alcohol, a heterogeneous group of non-exposed children with a variety of clinical conditions, and typically developing controls.

METHOD

DISCUSSION

BACKGROUND

• Results coincide with previous studies that have identified executive function as an area of impairment in children with prenatal alcohol exposure.

• In addition, the profile of impairment in executive function found in children with prenatal alcohol exposure differs from non-exposed children with a variety of clinical conditions.

• These findings suggest that measures of executive function could contribute to differential diagnosis between exposed and non-exposed groups.

• Further exploration of these deficits could refine the neurobehavioral profile of prenatal alcohol exposure to inform future identification and intervention efforts.

RESULTS

Demographic Data: Groups did not differ on race, ethnicity, sex, or age, but

did on handedness (p=.019), rate of ADHD diagnosis (p<.001), and rate of fetal alcohol syndrome (FAS) diagnosis (p<.001). As expected, groups differed significantly on General Conceptual Ability (GCA; AE<BCON<TCON, p<.001). See Table 2.

Between-Subject ANOVAs: Groups significantly differed on both TIA

[F(2,132)=10.709, p<.001] and TWA [F(2,132)=9.345, p<.001]. See Table 3.

Pairwise comparisons revealed that the AE group had significantly lower scores than BCON and TCON groups on both measures (ps≤.015). The BCON group had significantly lower TIA scores compared to the TCON group (p=.043), although these groups did not differ on TWA (p=.318).

Table 1. Description of Measures

Test Measure Ability Measured by Task

Total Initial Abstraction Scaled Score (TIA)

Level of abstract thinking: represented by the first question asked by an examinee on each item

Total Weighted Achievement Scaled Score (TWA)

Quantifies the number of questions asked until target is identified, but minimizes the effect of score inflation due to guessing

Table 3. Scores on TIA and TWA scaled scores in AE, BCON, and TCON groups [M (SD)]

Group TIA Scaled Score TWA Scaled Score

AE 8.2 (2.98) 8.6 (4.20)

BCON 9.9 (2.85) 10.9 (3.30)

TCON 11.2 (3.25) 11.6 (2.97)

Address for correspondence: sarah.mattson@mail.sdsu.edu

Table 2. Demographic information by group.

Variable AE(n=43)

BCON(n=43)

TCON(n=51)

Sex [n (%) Female] 18 (41.9) 13 (30.2) 22 (43.1)

Race [n (%) White] 29 (67.4) 30 (69.8) 36 (70.6)

Ethnicity [n (%) Hispanic] 15 (34.9) 16 (37.2) 19 (37.3)

Handedness* [n (%) Right] 38 (88.4) 31 (72.1) 47 (92.2)

Age in years [M (SD)] 13.8 (2.12) 13.0 (1.98) 13.5 (2.27)

GCA [M (SD)]* 85.6 (12.02) 101.7 (11.82) 108.4 (15.22)

FAS Diagnosis* [n (%) FAS] 7 (16.3) 0 (0) 0 (0)

ADHD Diagnosis* [n (%) ADHD] 29 (67.4) 19 (44.2) 0 (0)

* significant at the p < .05 level

Subjects: 137 subjects aged 10-16y (M=13.4) were recruited from the San Diego site of CIFASD III. Subjects comprised three groups: children with confirmed histories of prenatal alcohol exposure (AE group), non-exposed children with a variety of clinical conditions including ADHD (BCON group), and typically developing controls (TCON group).

Measures: Delis-Kaplan Executive Function System (D-KEFS):Subjects completed the Twenty Questions subtest from the D-KEFS, which assesses abilities in categorization, hierarchical processing, and problem solving strategies. Total Initial Abstraction (TIA) and Total Weighted Achievement (TWA) scaled scores were compared between AE, BCON, and TCON groups (See Table 1).

Statistical Analyses: Demographic data were analyzed using analysis of variance (ANOVA) and chi-square techniques. Group differences in TIA and TWA were analyzed using two one-way ANOVAs with group serving as the between-subjects factor. Significant group differences within the ANOVAs were followed up using pairwise comparisons.

Figure 1. Differences on TIA and TWA between AE, BCON, and TCON groups

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