Behavioral Inhibition in Boys with Sex Chromosome Aneuploidies Compared to a Clinical Sample

Abstract

Sex chromosome aneuploidies (SCA) in boys involve physiological, cognitive, and socioemotional challenges. Internalizing problems in boys with SCA are underexamined. We examined behavioral inhibition (BI) in boys with SCA, compared to a clinical sample. BI is a temperamental style characterized by shyness, withdrawal, and cautiousness, and represents increased risk for internalizing problems. Parents (76% mothers) completed the Behavioral Inhibition Questionnaire (BIQ; Bishop et al. 2003), which comprises total BI and BI in six specific domains. Parents of 25 boys with SCA participated (boys’ M age = 11.7 years, SD = 4.5, range 2–18 years), including boys with karyotypes 47,XXY, 47,XYY, 48,XXYY, and 48,XXXY. We compared their BI to 100 boys referred to mental health clinics and treated for anxiety (M age = 11.7 years, SD = 2.3, range 7–17 years), and to norms from 307 Australian boys aged >5 years. Total BI in boys with SCA was at the same level as clinic-referred boys (effect size difference d = 0.02), and higher than norms (d = 0.81). Boys with SCA were significantly more inhibited in physical situations than clinic-referred boys (p = .007; d = 0.71). Differences were small to negligible for BI domains involving peer, unfamiliar adults, and performance situations (all d ≤ 0.34). In conclusion, boys with SCA seem to be as behaviorally inhibited as boys treated for anxiety problems in mental health clinics. Inhibition in physical domains may be a particular challenge for boys with SCA.