Comparisons Between Black and White Children Included in the Autism Treatment Network Registry

Background:  Prevalence rates of ASD are lower in Black children (1%) compared to White children (1.2%). Black children are diagnosed at an older age. Whether or not underdetection is paralleled by differing clinical presentation is not known.

Objectives:  To evaluate differences between Black and White children in a large clinical sample of children referred for and diagnosed with ASD.

Methods:  Data collected in 18 ATN sites from 2007 to 2013 were obtained. We included in this analysis 244 Black subjects who were matched by gender, age and clinical site to 488 White children. They ranged in age from 1.5 to 15.9 years with no difference between Black and White children. There were 82.8% boys and 17.2% girls.

Results:  

There was no difference between Black and White children for their repartition by ATN site. Children from Black families had significantly lower parental education (chi-2=25.1, 5 df; p<.001). When assessed with the ADOS, both groups showed similar overall levels of autistic symptoms, as assessed by Calibrated Severity scores from the ADOS, that showed no difference for Social Affect, Restricted Repetitive Behavior, and Total scores (all comparisons: NS). However, item score analyses showed better Eye Contact in BIack children, fewer Vocalizations, more Stereotyped Utterances, and less Sharing. In younger children assessed with the Mullen Scales of Early Learning, Black children had significantly lower scores on the Early Learning Composite (52.1 vs 54.6; p=.03). Older children who had a Stanford-Binet abbreviated IQ score, showed similar differences, with Black children scoring lower than White children (61.7 vs 66.7; p=.08). Similarly, Black children with full Stanford-Binet assessments showed consistent trends (p>.05 and <.15) for having lower scores than White children with a 6- to 7-point difference on standardized scores. On CBCL scores, Black children showed significantly higher scores on the Anxiety Problems narrow-band scale (57.0 vs 55.2; p=.01), lower scores for Somatic Complaints (57.3 vs 58.9; p=.02), and no difference for Withdrawal, Attention Problems, Aggressive Behaviors, Internalizing, Externalizing and Total CBCL scores. With the exception of the Communication score that showed lower proficiency in Black children as compared to White children (61.9 vs 65.3; p<.01), all other Vineland Adaptive Behaviors scores showed no differences.  Antihistaminic drugs were prescribed more frequently in Black children (10.2% vs 4.9%; Fisher exact test: p=0.011); otherwise, no difference was found for prescribed drugs, including amphetamine derivatives, atomoxetine, alpha-2 adrenergic antagonists, anticonvulsants, SSRI’s, and atypical neuroleptics.

Conclusions:  Greater communication and cognitive delay, as well as anxiety symptoms, seem more prevalent in Black than White children in this referred sample. The limitations of a study relying on referred children only will be discussed.