Understandng the Relationship between ADHD and Depression in Children

Prior research with both community and clinical samples has documented that rates of depression are significantly higher in children with ADHD than in other children.  This is concerning because children with ADHD and depression, in addition to experiencing greater distress in the present are likely to have greater difficulty over the course of their development.

In children with both ADHD and depression, it is almost always the case that ADHD emerges first, and depression emerges later in development. This has led researchers to consider what it is about ADHD that might predispose children to develop depression. 

One prominent theory is that the relationship between ADHD and depression may result from the social/interpersonal difficulties that many children with ADHD experience.  These difficulties can lead important others in the child's life to develop negative appraisals of the child's social competence that are communicated to the child during the course of ongoing negative social exchanges.  With increasing age, these negative social experiences and others' negative appraisals can adversely affect children's view of their social competence, which, in turn, can predispose them to develop depressive symptoms.  An interesting study published recently in the Journal of Abnormal Child Psychology was designed to test this theory (Ostrander, Crystal, & August [2006]. Attention Deficit-Hyperactivity Disorder, Depression, and Self- and Other Assessments of Social Competence: A Developmental Study. JACP, 34, 773-787. 

Participants were 246 children in grades 1-4 that included 148 children with ADHD and 98 children without ADHD who served as controls.  Approximately 80% of participants were male and all were recruited based on screening results obtained in a large community sample.  Of the 148 children with ADHD, 60 also met criteria for either Oppositional Defiant Disorder (ODD) or Conduct Disorder (CD) while 88 did not.  (You can find information on diagnostic criteria for ODD and CD at www.helpforadd.com/co-occurring-disorders/ ).


- Measures -

The main constructs of interest were children's depressive symptoms, others' appraisal of children's social competence, and children's self-appraisal of their social competence.  These constructs were measured using a number of well-validated rating scales as described below.


Depression - Depressive symptoms were obtained from both children and their parents. Children completed the Child Depression Inventory (CDI), a widely used and standardized measure of self-reported depressive symptoms.  They also completed the self-report version of the Behavioral Assessment System for Children (BASC); the BASC includes a scale to measure depressive symptoms.  Parents completed 2 standardized and nationally normed behavior rating scales, the BASC and the Child Behavior Checklist (CBCL).  Both measures contain scales to measure parents' perceptions of depressive symptoms in their child. 

Child and parent reports of depressive symptoms were then combined to create an overall depression score for each child with higher scores reflecting greater depressive symptomatology.


- Social Competence -

Others' Appraisal - Parents and teachers provided appraisals of children's social competence using several different measures of this construct.  For parents, the Social Skills scale from the BASC and their ratings on the Social Skills Rating System were used to assess their perceptions of their child's social competence.  Teacher perceptions of children's social competence were derived from the Social Skills scale from the teacher version of the BASC and the Walker-McConnell Scale of Social Competence and School Adjustment.  Parent and teacher reports were averaged for each child to provide a composite social competence rating. Higher scores reflected higher ratings of others'-perceived social competence.


Self-appraisal - To assess children's views of their own social competence, each child completed the Piers Harris Self-Concept Scale, which includes a 12-item scale of perceived popularity.  Children also completed the self-report version of the BASC, which contains scales that assess the perception of having good social relationships, the stress and tension experienced in social relationships, and the feeling of being excluded from social activities.  These different scales were summed to create an overall measure of self-appraisal of social competence, with higher scores indicating greater self-perceived social competency.

RESULTS

- ADHD and Depression -

The authors first examined differences in depressive symptoms in 3 groups of children: those with ADHD only, those with ADHD + ODD/CD, and comparison children.  They examined this in both younger children (younger than 9) and older children (age 9 and above).

In both younger and older children, depressive symptoms were significantly higher among children with ADHD; this was true regardless of whether ODD or CD was also present.  The magnitude of the differences would be considered relatively large.  Among older children, depressive symptoms were highest when ODD or CD co-occurred with ADHD.

It is important to note that although children with ADHD had significantly higher scores on the depressive symptom composite, this does not mean that all, or even the majority of children with ADHD, were experiencing clinically elevated levels of depressive symptoms.  Instead, it simply indicates that the average depression score was higher for these children.  Unfortunately, the authors do not indicate the percentage of children in the ADHD group with scores that fell in what would be considered a clinically elevated range.  Thus, although these children were experiencing more distress than others, it is not clear how many would be considered clinically depressed.


- ADHD and Others' Appraisal of Social Competence -

At both younger and older ages, children with ADHD were viewed as having significantly lower levels of social competence by their parents and teacher.  Although there was some indication that children with ADHD plus ODD or CD had the lowest ratings, differences between these children and children with ADHD only were not significant.  Once again, the magnitude of the difference between children with and without ADHD would be considered large.


- Self-Appraisal of Social Competence -

Similar results were found for children's appraisal of their own social competence.  Children with ADHD, regardless of whether they also met criteria for ODD or CD, rated themselves as less socially competent than other children at both age groups.  There was a clear indication that the relationship between ADHD and negative self-perceptions of competence was stronger among the older children. 


- Test of Theoretical Model -

The final analyses conducted by the authors involved testing for hypothesized linkages between ADHD, others- and self-appraisals of social competence, and depression in younger and older children. 

Among younger children, the authors expected that the relationship between ADHD and depression would be mediated by others' perception of children's social competence.  In other words, they hypothesized that the reason children with ADHD have higher rates of depressive symptoms is because ADHD results in others developing negative views of the child's social competence, and these negative appraisals of others contributes to the development of depression.  This hypothesized model is shown below:


ADHD ===> Others' negative appraisal of social competence =======> Depression


Among older children, the relationships predicted by the authors were a bit more complex.  Here, they again expected that ADHD would lead others' to develop negative appraisal of the child's social competence.  Because older children are more sensitized and attuned than younger children to how others' view them, however, the negative appraisal of others was expected to negatively influence children's own appraisal of their competence, which, in turn, would lead to depressive symptoms.Thus, the model they hypothesized for older children is as follows:

ADHD ==> Others' negative appraisal ==> Negative self-appraisal ==> Depression


Although the statistical procedures used to test these relationships are a complex, the results obtained were reasonably straightforward.  For younger children, it was found that having ADHD predicted more negative appraisal of social competence by others, which, in turn, predicted higher rates of depressive symptoms.  In fact, about half of the relationship between ADHD and depression was explained by the negative appraisals of others. Thus, the model suggested by the authors was supported, although it is important to note that about half of the link between ADHD and depression did not depend on others' appraisals and is thus attributable to other factors, e.g., genetics, academic struggles, etc., that were not measured in this study.

The authors' model for older depression was also supported.  As predicted, ADHD predicted negative appraisal by others, which, in turn, predicted more negative self-appraisals, which, in turn, was associated with higher rates of depressive symptoms.  Nearly half of the association between others' appraisals and depressive symptoms was explained by the relationship between others' appraisals and self-appraisals, a relationship that was not evident in the younger sample.  As with younger children, there remained a direct relationship between ADHD and depression that could not be explained by the variables in the model.

SUMMARY AND IMPLICATIONS

Three primary findings were evident in this study.  First, there was a strong relationship between ADHD and depression - with and without co-morbid ODD/CD - in both younger and older children.  Among older children, the relationship between ADHD and depression was stronger when ODD or CD was also present.

Second, about half of the relationship between ADHD and depression in younger children was explained by the others' negative appraisals of social competence in children with ADHD.

Third, among older children, a more complex relationship emerged as children's negative self-appraisals - and not just others' appraisals of them - were important in understanding the linkage between ADHD and depression.

In interpreting the results of this study, it is important to recognize that demonstrating a link between ADHD, the negative appraisal of others, and depressive symptoms does not mean that parents and teacher "cause" children with ADHD become depressed because of their negative appraisals. 

Instead, I believe a more reasonable interpretation is that the difficult behavior that many children with ADHD exhibit contributes to ongoing difficulties in parent-child and teacher-child relationships.  These difficulties may contribute to parents and teachers viewing the child with ADHD as having poor social interaction skills. 

In some circumstances, these negative views may be directly communicated to the child, and this could certainly contribute to an increase in depressive symptoms over time. However, it is perhaps more likely that the ongoing negative interactions resulting from challenges that many children with ADHD present, and how these interactions come to affect the child's view of their relationships and themselves, is what contributes to an increase in depressive symptoms over time.  This view differs in important ways from one that "blames" parents and/or teachers for the distress that many children with ADHD experience. Instead, it recognizes that ADHD leads to conditions that increase the risk of other problems, such as depressive symptoms, emerging over time.  Interventions that target these conditions - such as repeated negative exchanges that lead others to develop negative appraisals of the child - may thus reduce the risk of such problems developing, even though the same
conditions are not related to the original core symptoms o
fADHD.

The authors point to several limitations to their study that should be considered.  Most important is that all data was collected at a single time point, rather than thru a longitudinal design.  Given the developmental nature of their hypotheses, studying the relationship between ADHD, others' and self-appraisals, and depressive symptoms across time will be very important to do.

They also note that because their participants were derived from a community sample, it is unclear whether the results reported would generalize to a clinic sample or represent children who have more severe levels of depression such as those with a formal diagnosis.

These limitations not withstanding, this study makes a useful contribution to our understanding of the link between ADHD and depressive symptoms in children, and suggests targets for intervention that may reduce the strength of this association.