Earlier this year, the journal Pediatrics published the second autism supplement produced by the Autism Speaks Autism Treatment Network (ATN) in its federally funded role as the Autism Intervention Research Network on Physical Health (AIR-P).
The special issue’s 17 groundbreaking articles included “Medical and Behavioral Correlates of Depression History in Children and Adolescents with Autism Spectrum Disorder.”
The study followed up on previous research suggesting that depression is particularly common among teens with autism – and perhaps younger children on the spectrum. Research had likewise suggested that depression could have different causes and/or produce different problems in those affected by autism. For these reasons, the Autism Speaks ATN prioritized a deeper look at the issue with an aim to provide guidance for the nation’s physicians and therapists, as well as young people on the spectrum and their parents.
We invited the senior author of the study, clinical psychologist Katherine Gotham of Vanderbilt University Medical Center, to answer some questions raised and addressed by her team’s research. Vanderbilt is one of 14 centers in the Autism Speaks ATN.
Autism Speaks: When did it become clear that depression is particularly common among teens on the autism spectrum?
Dr. Gotham: For years, we’ve had mixed reports on how common depression is among children and teenagers with autism spectrum disorder. But the numbers depended on who you looked at. If you looked at children receiving specialized care – say, in the ATN or other autism clinics – you would see higher rates of depression than if you looked at, say, the school records of children with autism. Presumably, the school records include many children who have never been evaluated for depression. So the school sample might miss many cases and produce an underestimate. We might also see higher rates among children and teens being seen at ATN clinics for associated medical issues, given the stress these conditions can cause.
It’s hard to get to the bottom of how common any co-occurring condition is unless you study all children with autism in a certain place and follow them over time. But this type of study is rare because it’s expensive and difficult.
Still, we knew that many parents report being concerned about depression in children –especially teenagers – with autism. We also had accumulating evidence from research studies that depression is more common among children with autism than it is in the wider child and adolescent population.
Our study helped confirm many of these impressions. For instance, 20 percent of the teenagers in our study had been diagnosed with depression at some point in their lives, according to their parents. By contrast, a large national survey recently found that just 8 to 12 percent of teens in the general population had ever received a diagnosis of depression.
Autism Speaks: Going into your new study, what did we know – and not know – from research on the connection between autism and depression?
Dr. Gotham: We didn’t have very much information on what caused depression among kids with autism. However, several research groups had suggested that the connection might stem, at least in part, by kids with autism becoming aware of their social challenges. Loneliness and bullying likely play roles as well. We also wanted to explore possible links between depression and the medical issues and behavioral challenges that commonly occur with autism.
Autism Speaks: What gap or gaps in knowledge was your study aimed at addressing?
Dr. Gotham: We were particularly interested in a small body of research suggesting that depression is particularly common among children and teens whose autism is complicated by one or more of the behavioral or medical issues that frequently occur with autism. These include attention deficit hyperactivity disorder (ADHD), gastrointestinal problems, sleep disturbances or self-injurious behavior. Some of this research had linked these medical and behavioral issues to depression in both typically developing children and those with autism.
Our group, led by Jessica Greenlee and Angela Mosley, wanted to look at possible associations between these conditions and depression in the large group of children and adolescents enrolled in the research registry of the Autism Speaks Autism Treatment Network. We felt this was a great opportunity to increase understanding of what contributes to depression in kids with autism. Down the line, this might help to shape our thinking about how to best treat or prevent depression among these children.
We also hoped to identify any characteristics, or “red flags,” that might suggest that certain children with autism are at particular risk for depression. This information is important for helping pediatricians and other healthcare professionals recognize when they should screen a child who has autism for depression - and treat or refer to a specialist as appropriate.
Autism Speaks: How did you gather your information on depression among children and teens with autism?
Dr. Gotham: At all 14 centers in the Autism Speaks Autism Treatment Network, we ask parents whether they would like to enroll their children in our research registry. This includes making their children’s medical records available for research in a confidential manner.
As part of the healthcare we provide, we also ask parents whether their child has ever received a diagnosis of depression. In our study, we estimated the prevalence of depression based on parent responses to this question.
One limitation to this approach is that it may still underestimate the true prevalence of depression in the children and teens seen in the ATN. We know, for example, that many kids who go through a depressive episode never receive a formal assessment or diagnosis of depression. So we’re missing those kids in our count. In addition, some parents answered “unsure” when asked about a diagnosis of depression. We didn’t count them either.
Despite these two areas of possible undercounting, we still found depression rates that were higher than the norm. Around 5 percent of the 6 to 12 year olds with autism had been diagnosed with depression. As mentioned earlier, this rose to 20 percent of 13 to 18 year olds.
On the other hand, some parents might have answered “yes” if they felt sure that their child had been depressed at some point – even if that episode might not have warranted a medical diagnosis of depression.
Autism Speaks: What are the key take-home findings of your study for medical professionals?
Dr. Gotham: It can be difficult for some providers to see beyond an autism diagnosis. So the first take-home message is that healthcare professionals should be aware that a significant number of children and teenagers with autism become depressed. As educators and healthcare providers, we should work with parents to keep an eye out for symptoms of depression in this special group of young people.
As a related take-home point, we hope that the findings of our study will encourage healthcare professionals to consider screening for depression as a routine matter among young patients who have autism complicated by medical and behavioral issues such as GI problems, seizures or aggression. We found significantly greater – more than doubled – odds of seizure disorders and gastrointestinal problems among the children and teens who had been diagnosed with depression, compared to those who had not.
Our study also found that depression tended to be more common in older children and those with higher IQ. So it may be particularly important for physicians to screen for depression among older and more cognitively able children on the autism spectrum.
Autism Speaks: Similarly, what are the key take-home findings for parents of children or teens with autism?
Dr. Gotham: Again, the take-home message is about greater awareness and attention. Sadness, irritability or aggressive behavior, lack of interest or pleasure in things that a child typically enjoys – these can all represent something beyond “just autism” or “teenage moodiness.” A noticeable intensification of special interests or a switch to focus on “dark” topics can likewise be warning signs of depression.
These warning signs can differ among children, so it’s important for all parents to be aware of the possibility of depression in children – especially teenagers – who have autism.
Autism Speaks: What changes or advances in medical and mental-health care would you like to see from your team’s report?
Dr. Gotham: In the short-term, we hope that this report encourages awareness of and screening for depression in children and adolescents who have autism.
We also hope our report both builds on previous studies and guides future studies that will increase our understanding of how to recognize depression among children and teens who have autism. We likewise hope we’re helping to deepen understanding of what causes and maintains depression in these children.
Autism Speaks: What additional research would you like to see?
Dr. Gotham: The field of autism healthcare – and the families it serves – would benefit from:
* Studies exploring what depression looks like in people with autism across the lifespan and across ability levels
* Studies evaluating the effectiveness of different interventions for depression among children, teens and adults with autism. If necessary, how should we be adapting existing treatments for depression for those who also have autism?
* And more research into what causes or maintains depression among people autism – leading to greater understanding of how to best treat their depression and improve their quality of life.
For more on autism and depression, also see:
What’s the connection between autism and depression?
For more on this year’s ATN/AIR-P supplement to Pediatrics, see: