IQ and Internalising Symptoms in Adolescents with ASD

Abstract

Intelligence quotient (IQ), has been found to relate to the presence of internalising symptoms in autism spectrum disorder (ASD). This meta-analysis sought to clarify the direction of the relationship between IQ and two prevalent internalising symptoms, anxiety and depression, in adolescents with ASD. Secondly, this study aimed to highlight methodological factors contributing to inconsistent findings in existing research. Self-reported anxiety was found to be significantly higher in youth with a lower IQ, while depression was positively associated with IQ. Consequently, parents, schools and clinicians should be cautious of underestimating anxiety in youth with a lower IQ. However, care should also be taken to ensure adolescents with ASD without intellectual disabilities are not overlooked with regards to social and emotional support.

IQ trajectories in autistic children through preadolescence

“…Only the CHG group experienced significant reductions in externalizing symptoms between T1 and T3. While internalizing scores in P‐High and CHG did not increase with the beginning of adolescence as might be expected (Solomon et al., 2012 ), the ID group experienced some reduction in these symptoms, as has been found by others (Edirisooriya et al., 2021 ). However, it is not clear that internalizing symptoms, and especially anxiety, can be well measured for children with intellectual disability (Kerns et al., 2021 ), so these findings must be interpreted with caution.…”

Patterns of psychopathology and cognition in sex chromosome aneuploidy

“…However, there is growing recognition that correlations between different dimensions of cognition and psychopathology can be weak at the population level and require large sample sizes to be reliably estimated [64], which poses a particular challenge for estimating such correlations within individually rare SCA subgroups. Nevertheless, it is notable that some of the relationships between IQ and psychopathology that have been reported in other datasets (autism spectrum disorder [65];, and anxiety [66];)-were not apparent in SCA. Thus, there remains an open question as to whether relationships between IQ and psychopathology show substantial variation between different clinical subgroups.…”

Association of cognitive and adaptive skills with internalizing and externalizing problems in autistic children and adolescents

“…Findings from two recent meta‐analyses illustrate well how conclusions may differ depending on whether studies include children with co‐occurring ID and whether IQ scores are used as a continuous or categorical variable. Edirisooriya et al (2021) examined the relationship between IQ scores and two distinct internalizing problems (anxiety and depression) in young autistic adolescents ( n = 812) (Edirisooriya et al, 2021). Although no significant overall association between IQ scores and parent‐reported anxiety was found, when researchers split the sample by IQ score, they found a very small negative association for those above 70 (suggesting anxiety increases as IQ decreases in those with IQs in the 70+ category) and a small positive association in those with an IQ score below 70 (suggesting an increase in anxiety as IQ scores increase for those with an overall IQ score below 70).…”

“…Findings from the Edirisooriya et al (2021) and Mingins et al (2021) reviews suggest overall small to very small associations between IQ scores and anxiety symptoms, though there still remains lack of clarity regarding the direction and magnitude of this association; as illustrated above different conclusions are reached depending on whether IQ scores are considered (as either continuous or categorical classification) and/or whether ID is considered. Further, the presence of a small, positive association between IQ scores and depression in the Edirisooriya et al (2021) meta‐analysis—contrasting with the near zero and non‐significant association with anxiety in the same study—suggests that the use of narrowband diagnostic constructs, such as depression and anxiety, can lead to different conclusions regarding associations with cognitive skills. Broadband classifications of symptoms (into internalizing and externalizing problems) is both empirically validated (Achenbach, 1966) and an approach that reflects better the fact that autistic individuals experience symptoms that come under separate diagnostic categories.…”

“…Potential confounders were age and sex (to control for their association with internalizing and externalizing problems in autistic children and adolescents; Oswald et al, 2016; White et al ., 2009), as well as occurrence of seizures, known to impact cognition, mood and behavior (Helmstaedter & Witt, 2017). Based on existing literature (Neuhaus et al, 2018), we anticipated cognitive skills scores would have small, positive associations associated with internalizing problems although no hypotheses were made on whether this association would be replicated when examined separately in participants with co‐occurring ID, because of the conflicting findings (e.g., Edirisooriya et al, 2021; Mingins et al, 2021). On the basis of existing evidence of no differences in the levels of externalizing problems between autism and autism with co‐occurring ID (Goldin et al, 2014; Totsika, Hastings, Emerson, Berridge, & Lancaster, 2011) we anticipated a similar pattern of associations between cognitive scores and externalizing problems across children with and without ID.…”