Freelance journalist Jo Carlowe and Olga Eyre discuss depression.
Olga draws from her research to highlight the importance of awareness and depression in relation to neurodevelopmental problems with a specific focus on ADHD. They also discuss irritability, how it manifests, when it’s an issue and new research showing an increased likelihood of developing depression symptoms later in life.
Links to studies and resources
Olga Eyre is a WCAT Fellow (Wales Clinical Academic Track) and CAMHS trainee in South Wales. She recently completed her PhD examining links between irritability and depression in children with ADHD and other neurodevelopmental difficulties.
Interviewer, Jo Carlow
Interviewee, Dr. Olga Eyre
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Interviewer: Hello. Welcome to the In Conversation podcast series for the Association for Child and Adolescent Mental Health or ACAMH, for short. I’m Jo Carlow, a freelance journalist with a specialism in psychology. Today I’m interviewing Olga Eyre, a clinical research fellow at the Division of Psychological Medicine and Clinical Neuroscience at Cardiff University. Today we’re going to focus on depression in children and young people. Olga, welcome. Thank you for joining me. Can you start with an introduction about who you are and what you do?
Dr. Olga Eyre: Yes. I’m an academic child and adolescent psychiatry trainee, based in south Wales. And what that means is that whilst I’m training to be a child and adolescent psychiatrist, I also have some time allocated to training and undertake research. And this research training programme has allowed me to actually undertake a PhD during my training which I finished in the last six months. And my PhD involved researching the links between irritability and depression in young people with ADHD and other neurodevelopmental difficulties. And now that my PhD is finished, most of my time at the moment is actually spent in clinic, gaining clinical experience in child and adolescent psychiatry.
Okay. We’ll focus a bit more on your research shortly. But can you tell me what prompted your interest in this line of work and study?
Dr. Olga Eyre: Yes. Well, I’ve always been interested in psychiatry, even as a medical student. And I actually took a year out during medical school to do an inter-collated degree in psychology, where I also managed to learn more about research and research method. Following on from that, I did do a psychiatry rotation, soon after I graduated as a doctor, which I really enjoyed.
But I guess the time that I really became interested in child and adolescent psychiatry and research into child and adolescent psychiatry, particularly depression, was about ten years ago. At that time I took a job as a research assistant at Cardiff University and I worked on a large study that looked at identifying risk factors for adolescent depression. So, that study was called the Early Prediction of Adolescent Depression study. The job I did then involved me travelling round the UK and undertaking interviews with parents and young people. And I loved being a part of the research team and I found the research itself really interesting. So that definitely influenced my career path, I suppose. And it encouraged me to train in child and adolescent psychiatry, as well as to be involved with research. And actually, following on from that, obviously I’ve gained clinical experience in psychiatry and my interest has grown, and I’ve become more interested in researching both ADHD and depression. And, in particular, trying to understand why young people with ADHD are at increased risk for depression.
Just focusing on some of that earlier research, you looked at the impact of parental depression on children and there was a paper in the British Journal of General Practice in which you called for increased parental and professional awareness that mental health problems can cluster in families and for the need for early intervention. That was in 2012. Has awareness improved since then?
Dr. Olga Eyre: Well, I suppose it might be worth telling you a bit about that work that we did that you mentioned from the British Journal of General Practice. That was part of the work I did with the Early Prediction of Adolescent Depression study that I just mentioned. And that study involved recruiting parents with recurrent unipolar depression who also had a child between the age of nine and 17. So we were really recruiting families where there were children at high risk of developing depression because we know children of depressed parents are at increased risk. And these families were followed up over four years at three different timepoints. And we were able to collect information about the presence of psychiatric disorder in these children, as well as information on whether these children had accessed services. Specifically, we were able to look at whether children with psychiatric disorder were accessing services when they should be.
We actually found that only around a third of children who met criteria for psychiatric disorder at the time of the study had been in contact with any service in the three months before. So even though the parents were known to primary care and GPs for their own depression, these children weren’t being picked up or seeing services. And, as you said, at that point when we had these findings, we called to improve awareness in mental health problems in young people and the fact that they might cluster in families, really in order to allow these children who were developing disorders to be detected earlier.
Why were they barred from services or not accessing services?
Dr. Olga Eyre: We did look at that in the paper. We tried to look at barriers to service access. And we didn’t find much other than really that the young people whose parents were less concerned or had fewer worries about their children were less likely to access services. I suppose you would expect if you have parents going and seeing GPs about their own depression, that people might be aware of the children being at increased risk. But it didn’t seem, clearly, most of the children were not being referred on. So I think part of it is probably about awareness. And, like we said, that is important to improve. And you asked me whether awareness has improved and, actually, I think it’s quite difficult to measure that. But studies more recent than that one in 2012 continue to show that there are low rates of service use in young people who do have a diagnosable disorder. There’s evidence to really suggest that children are still not accessing services and maybe that the awareness isn’t actually there yet.
Right. And we’re talking about professional awareness here, from GPs, rather than from the parents.
Dr. Olga Eyre: Yes. And I think it’s probably a combination of things, really. Because obviously, GPs, these families are in contact with GPs, but we’re also looking at children accessing not just medical services but accessing school, having… Across the board. So non-medical as well. So it looks like the lack of awareness may be there across various settings, really.
What more needs to be done then, given that there still seems to be issues around access and professional awareness?
Dr. Olga Eyre: It’s not easy, I don’t think. I guess we’re speaking about awareness and I think that is probably still key. Like we said, not just awareness from GPs and medical professionals but also young people themselves having an understanding, as well as peers and parents and carers and, really, any agencies that are working with young people, so including education as well, who can help to identify mental health symptoms. Anyone who’s in the position to be helping to refer children on, I suppose. And also increasing engagement of young people, allowing them to feel comfortable to come and talk to people about any mental health difficulties that they have as well.
Has that improved slightly, particularly in schools and educational settings?
Dr. Olga Eyre: I think people are trying. Everyone is definitely, it seems to be mental health is important. It seems to be on the agenda across the board, really. And schools are seeing a lot of difficulties in young people. But I’m not sure about how measurable it is and how easy it is to see whether awareness has improved or not.
Right. Olga, as we mentioned earlier, your more recent work has focused on depression and children with neurodevelopmental issues. Are children with neurodevelopmental difficulties at greater risk of developing later adolescent depression?
Dr. Olga Eyre: Yes. So, evidence from the research does suggest that children with ADHD definitely are at increased risk of developing depression. Findings across studies do vary but there have been meta analyses that suggest there is an association between ADHD and depression. In terms of the other neurodevelopmental disorders, there is also some evidence to suggest there’s elevated depression symptoms and diagnoses, in particular, such as autism spectrum disorder. There does seem to be evidence to suggest that there is a link between neurodevelopmental disorders and later depression.
And does anybody know why? Probably a really difficult question.
Dr. Olga Eyre: Yes, it’s a difficult question. I suppose there’s not a clear answer to that. It’s something that I’m really interested in. There are a number of possible explanations why a child with ADHD, for example, might be at increased risk of developing depression. One reason could be that children with ADHD and depression might share, that neurodevelopmental disorders and depression, might share risk factors. So there might be shared genetic or environmental risk factors for both the disorders. And there is some evidence to show that there’s shared genetic risk between ADHD and depression. So, for example, family members of those who have ADHD are more likely also to have depression than those without ADHD. And other genetic study designs, twin studies and molecular genetic studies, have also suggested there is some genetic overlap between ADHD and depression. So that’s one possible reason why we might see them co-occurring, ADHD and depression.
But there’s other theories and possibilities. One possibility is that having ADHD itself could increase the risk for developing depression. So people have suggested that children with ADHD who have a demoralisation related to their ADHD symptoms may be at increased risk of becoming depressed. And we know that having ADHD can actually impact on peer relationships, family relationships, it can affect the child’s achievement at school. And I guess all those factors can contribute to increased risk of depression as well. And there has actually been some work done in the department in Cardiff recently by another PhD student, Vicky Powell, and she found that peer relationships and academic achievement partly could explain the relationship between ADHD symptoms and later depression symptoms in a big population sample. So there is some evidence for this theory. But it’s not that straightforward. Because some others haven’t actually found an association between ADHD-related impairment and later depression. So not completely clear. But you could see how that might happen, really.
And I guess the thing that is relevant really to some of my work is that whether there’s the presence of another disorder or another difficulty that might explain the association between, say, ADHD and depression. So, for example, anxiety is common in children with ADHD. It’s also robustly associated with depression. So it could be that having anxiety could explain that link between seeing both ADHD and depression together. And, so I’ve said anxiety’s an example. That’s quite a clear one. But as I’ve mentioned, I’m quite interested in irritability. And we know, actually, from research that irritability is really common in ADHD and longitudinal population studies have shown a link between irritability and later depression. So, irritability itself could explain the association between ADHD or other neurodevelopmental difficulties and later depression. And that’s actually really what I’ve been focusing most of my research on. So really looking to see whether irritability is important in explaining any association between neurodevelopmental difficulties and later depression. That’s my key interest.
But, yes, you’re right. It’s not actually very easy or very clear to know why ADHD or neurodevelopmental problems are associated with later depression. But I suppose I’d like to say that, although it’s not clear, it’s actually quite important for us to try and understand. And the reason for that is because children who have ADHD and depression together will actually have poorer outcomes. So it’s not just an interest to try and understand it. It’s actually important for the young people, I think. Because if you could try and identify those with ADHD who are at risk of depression and try and have some sort of intervention that could prevent the onset of depression, that would, in the long term, hopefully, improve the outcomes for these children.
I want to take you back one step. You talked about your research on the role of irritability. What does irritability look like? How does it manifest in this particular group?
Dr. Olga Eyre: Yes. So, irritability is really characterised by a proneness to anger. So when we’re looking at irritability in childhood, we’re talking about anger that’s disproportionate to the situation. And in the research that we’re doing, this irritability has to be inconsistent, really, with the child’s developmental level. So, irritability is relatively common in toddlers and young children. As you get older, it gets less common. And really, for it to be abnormal, it needs to be inconsistent with what you’d expect for a child of a particular age.
In the studies that I’ve been involved in, I’ve looked at measuring irritability in a couple of different ways. So, firstly, I’ve looked at irritable symptoms that form an irritable dimension of oppositional deviant disorder and so that specific symptoms that are the irritable symptoms of ODD are the child having temper tantrums or being very touchy and easily annoyed or angry and resentful. So they’re the key symptoms I’ve been looking at. And I’ve been able to make a score for each individual to see what level of irritability they have.
Right. Is that measured against age? Because you might expect that, as you say, in a toddler but…
Dr. Olga Eyre: Yes. Well, I’ve been looking, yes, specifically at particular ages. So in childhood I’ve been looking, so, in one of the samples at age ten and in another at age seven. So it’s quite specific, the age that I’m looking at. So, and I guess that is the irritable score but the other way that I’ve been really measuring irritability is using a diagnostic category. So, in the DSM 5, there’s a new diagnosis of disruptive mood disregulation disorder. DMDD, as it’s shortened to, is really a quite severe level of irritability, really, so you have to have severe temper outbursts that are really out of proportion and intense in duration to a particular situation.
But not just do you have lots of severe temper outbursts, the child has to have persistently irritable or angry mood between those outbursts. So it has to be there nearly every day, most of the day. And it has to have been present for at least a year. It has to be there across various settings. And really the onset needs to have been before the age of ten. So I suppose what I’m trying to get across is that the irritability that I’ve been measuring and looking at, thinking about children who’ve got really significantly impairing irritability.
Can you talk more through the findings of your research? What has it shown so far?
Dr. Olga Eyre: Yes. So, as I’ve said already, the main aim of the research was to look at the role of irritability in the association between ADHD and other neurodevelopmental difficulties and the development of later depression. And in order to try and answer this question, I’ve used both a clinical ADHD sample and a longitudinal population sample as well. So for the clinical ADHD sample, where all the children had a diagnosis of ADHD, a clinical diagnosis of ADHD, I looked both cross-sectionally and longitudinally at the association between childhood irritability and symptoms of depression. And what we found was that, irritability in childhood in this group with ADHD was associated with symptoms of depression, both cross-sectionally, so at the same time point, and then also in the future, longitudinally. And the thing that also came out of it, really, was that it seemed to be those that had persistent irritability across childhood and adolescence that were at particular risk of developing depression symptoms later. So those who had it across time. So that was the clinical sample.
And ‘later’ still being in childhood?
Dr. Olga Eyre: Yes. So we’re looking at… The follow-up, they had an average age of about 14. So we’re still looking at, actually, quite early adolescent depression symptoms, really, which is relevant too, yes.
And is anything known about the mechanisms involved in this association?
Dr. Olga Eyre: So we don’t really know why irritability is associated with depression in those with neurodevelopmental difficulties. So I told you about the results from the clinical ADHD sample. We found similar results in a large population sample, when we looked at neurodevelopmental difficulties broadly, that irritability was really important in explaining the link. But we don’t know really why. And again, it’s a really important question because if we want to try and develop effective treatments and prevent the onset of depression, we need to actually understand why irritability is linked with depression. And again, like we spoke about with the links between ADHD and depression, there’s again some evidence to suggest that genetic factors might be relevant. There’s been evidence to show that family history of depression is associated with irritability, both in the general population and in those with ADHD. And, again, twin studies have suggested that irritability and depression may have some common genetic underpinnings. Although it isn’t entirely consistent. We actually did some research in Cardiff as well looking at molecular genetic risk for depression and looking to see whether it was linked to irritability in our ADHD sample and we didn’t find that. So again, more work’s needed in terms of looking at genetic factors.
But I suppose environmental factors may also be of relevance as well. So if you have… We know, for example, that stressful life events, in particular stresses affecting relationships, are important risk factors for adolescent depression. And research is starting to show, really, that irritability is linked with impairment in lots of areas of functioning but one of those is family relationships. As you might imagine, a child that’s really irritable, it might have an impact on interactions with others. So it’s possible, I suppose, that irritability could predispose young people to having family relationship problems which may go on to predispose to depression. There’s quite a number of other risk factors associated with depression that haven’t necessarily been investigated but could be associated with irritability. So again, more research is needed into this. And, like I’ve said, it’s something that I’m definitely really interested in.
Is there an inevitability to this association? So the association between irritability and later depression in this group. Or can interventions be put in place that make depression in later adolescence less likely in these children?
Dr. Olga Eyre: Yes. So, not all children with irritability in childhood will go on to develop depression. I did mention that our research suggests that it’s probably those who have persistent irritability over time that are actually at greater risk for developing depression. This is definitely at least what we’ve shown in our sample of children with ADHD. So it’s not inevitable. But saying that, in terms of thinking about interventions that can be put in place, it feels we’re at a very early stage here. There’s still a lot of work to do. And like I said, it’s actually trying to understand why irritability is linked with depression is going to help with trying to develop interventions.
So, I suppose, for example, if you had evidence to suggest that irritability actually itself caused depression, for example, through difficulties with relationships, etc., potentially then if you could treat irritability, you might prevent the onset of depression. So then the focus would be on trying to make sure developing treatments for irritability. But if you found, for example, that irritability was associated with depression because of other shared environmental risk factors, then you’d be better off maybe targeting those risk factors in order to prevent depression onset. So we just need to understand more about the mechanisms, really, before we can really develop the interventions. But there is some evidence at the moment in young people with ADHD, that treating their ADHD with stimulant medication can actually improve symptoms of irritability. And treating these children with stimulant medication has also been shown to reduce the risk of onset of later depression. So there’s some clues and that’s compatible with the idea that, actually, reducing irritability may result in reducing risk for depression. But conclusions can’t really just be drawn from that. And there’s quite a lot more work that is needed to be developed, really, I think, before we can make conclusions.
So given the number of unknowns how can findings such as yours be translated into clinical practice?
Dr. Olga Eyre: I suppose the main one would be the fact we’ve observed that childhood irritability is associated with depression in the clinical sample of children with ADHD. And that, to me, has quite potential clinical implications because children with ADHD are often already under services. So they might be under child and adolescent psychiatric services or community child health services, particularly if they’re on medication for ADHD. So they’re already being seen and monitored. So knowing that children who have irritability, particularly persistent irritability, are at increased risk for depression, knowing that means that when they’re coming to clinic, it’s something that could be at least thought about and if you know these children are at particular risk, then thinking about at least asking them about mood symptoms could actually help to detect any depression early. So it would improve with earlier identification and treatment. And I think that is quite important.
Is that starting to happen already?
Dr. Olga Eyre: I don’t know, really. Obviously, I’m aware of the risk for irritability and the research into irritability has become more prominent in the last few years, definitely. Specifically looking at irritability and links with depression in children with ADHD and neurodevelopmental difficulties is building on the previous work on irritability in the general population. So I think if people are aware of these findings then, potentially, I think that’s something that would be easy to do, definitely. Just for ADHD. Our findings, like I said, in the population sample were for a broader group of neurodevelopmental problems, including ASD. So although that wasn’t a clinical sample where we found the links in children with ASD, it’s still, again, worth thinking about irritability in that group too. So I think the findings are relevant.
Olga, what other research areas are coming up for you?
Dr. Olga Eyre: At the moment, most of my time is spent in the clinic, really. But my aim is to try and take forward some of the findings from the research I’ve described already and try and actually understand more about why irritability is associated with depression. And I’ve mentioned that there’s a number of possible reasons why they might be linked. And I guess I’m really most interested in trying to see if there’s evidence to support any sort of causal relationship between irritability and depression. So epidemiological approaches to try and do this. But I guess I’m just in the early planning stages of the work, having just finished the bulk of the PhD. But that’s what I’m looking at and certainly interested in at the moment.
Right. Is there anything else in the pipeline that excites you?
Dr. Olga Eyre: Well, I guess, working in the department in Cardiff and having academic time as part of my clinical training is fabulous and it gives me loads of opportunities to be involved in a range of projects. But I guess probably the exciting news for the department in Cardiff, recently, was they’ve been awarded funding for a new Wolfson centre for young people’s mental health. So this centre actually aims to focus on reducing anxiety and depression in young people. And so it’s really, really relevant to the work that I’m interested in. So it’s quite exciting, really. And I think it’s aiming, really, to try and understand better about how anxiety and depression develop and thinking about the role of genetic and environmental factors. But also looking at intervention. So as you can see, it’ll be exciting to be working alongside that, really.
Very much so. Is there anything you’d like to add that I haven’t asked you?
Dr. Olga Eyre: The work I’ve touched on, it’s been focused specifically on childhood irritability. So I think it’s important to take that into account. Because I think that there is emerging evidence that’s really interesting, actually, that childhood irritability may actually differ from irritability that has its onset in adolescence or adulthood. So I think we can’t really assume… There’s a developmental perspective to be taken, really. We can’t assume all irritability is the same across different stages of development. And so, definitely, the findings we have here are relevant to links between childhood irritability and the early adolescent depression. So I just wanted to point that out, really.
Can you describe how it differs?
Dr. Olga Eyre: It’s quite recent research from, particularly, Lucy Riglin, who’s one of the postdocs in the department in Cardiff. She’s been looking at irritability trajectories and finding that irritability that starts early in childhood and persists across time seems to be more associated genetically with ADHD as well as ADHD symptoms. Whereas the irritability that starts in adolescence, so, starts a bit later and increases over time, is more strongly associated with depression and higher genetic loading for depression. So it’s really interesting work but it shows that a developmental perspective is really important in this research.
Right. And is there anything in terms of that trajectory? If it starts early, is there some sense that, put it in crude terms, that a child might grow out of it?
Dr. Olga Eyre: So there will be some children where irritability starts early and then they do grow out of it. And for others, I suppose… and these are the ones that seem to be more linked to the ADHD genetics… are the ones that start early and continue. It looks like there’s different patterns of irritability that can be described across time. The two that I mentioned are the ones that were really quite interesting.
It sounds like a really rich area for future research. Olga, what is your takeaway message for those listening to our conversation?
Dr. Olga Eyre: I suppose a few key points, maybe. That it’s important to identify and treat depression in adolescence early. That irritability may well be a marker of increased depression risk in those with ADHD and other neurodevelopmental difficulties. And that, actually, assessing irritability in children with these difficulties might allow for early identification and treatment of depression. And that, finally, we need to do more to try and understand why irritability is associated with depression in these young people.
Right. Olga, thank you ever so much. That was really fascinating. For more details on Olga Eyre, please visit the ACAMH website, www.acamh.org and Twitter @acamh. ACAMH is spelt A-C-A-M-H.