What is ADHD?

What exactly do we know about ADHD? Here’s Jo Steer, a consultant clinical psychologist and author of 'My Unique ADHD World' and editor of Understanding ADHD in Girls & Women...

Jo - So we are really talking about 5% of the population that we think have ADHD, so attention deficit hyperactivity disorder. It can vary across countries, which is interesting in terms of where it's being identified more. And if we look more to America, the rates are more like 10%, but in the UK it's around 5% of the population.

Chris - And if we consider children and adults separately, is it the same 5%? Do you have this as a child and turn into an adult with it or do we get some children who it goes away and some adults who are newly diagnosed or both?

Jo - Broadly speaking, we talk about ADHD as a neurodevelopmental condition or disorder. And what that means is it's lifelong, and it impacts on your brain. It's the way your brain functions. And this means that if you are a child and you are identified as having ADHD, you're very likely to continue to have that into adulthood. It might look differently and impact differently in your adult life or even throughout your childhood. Those symptoms can shift and change slightly depending on the demands that are being made on you, but also depending on the support that's around to help you with the difficulties you struggle with. So it can look different at different points. It's really important to remember that. And what's also of note is that we're finding more and more adults are now coming forward and identifying that they need an assessment for ADHD and they weren't identified in childhood and potentially they have had those difficulties all the way through their life. That's part of the criteria. We need to see evidence that these difficulties were there before the age of 12 years. And many of these adults can tell us in lots of detail that they've had lifelong concerns around attention and hyperactivity and impulsivity, but they're only now coming forward for an assessment. Perhaps just learning about ADHD for the first time or feeling confident enough to ask for that assessment even though they might have actually been struggling throughout the whole of their childhood adolescence and into their adult lives.

Chris - Do we know anything about risk factors? Is it more common in families? Is one gender more likely to have this than the other? What do we know about that aspect?

Jo - Definitely know that it runs in families. We do see a genetic link. So we do see children whose parents have symptoms, perhaps they may not have been diagnosed, but certainly have some of the symptoms or even families where more than one sibling have the difficulties. Sometimes, it might not be the immediate family that all have ADHD or a number of people have ADHD, but a more extended family. So if you look out to cousins or aunties and uncles. But it is really common and it's definitely a risk factor that someone in the family may be neurodiverse and have ADHD. However, there are also times when I assess children and adults and they come and they can't identify anybody within their family that has similar difficulties whether they've been diagnosed or not. So it's not a given. And I always say to young people and adults that just because you have ADHD doesn't mean that you will go on to have a child who has ADHD, but it does increase the risk, absolutely. There can be other factors that increase the risk as well, but nothing is causal. So there isn't one thing that we know if this happens, this definitely causes ADHD. So children that are born prematurely, babies that are born prematurely have an increased risk of ADHD, but not all babies that are born prematurely will have ADHD. So there are factors like that that can play into the situation but are not causal.

Chris - What about imaging studies? If we put people in brain scanners, does anything leap out?

Jo - We do know that there are differences in the brains of people who have ADHD and people who don't. And those differences can be in the structure of the brain as well as the neurochemistry of the brain. Now what's really interesting is at the moment where we're at, we can't pop someone in a brain scanner and do the neuroimaging and say, 'right, we can see you've got ADHD.' So it's not visible on an individual basis. But when we analyse groups, so a group of people who have ADHD and their brain scans and a group of people who don't, that's when those differences do show up. I hope in years to come, we may progress and find that we are able to use those brain scanners to help us identify these differences more clearly on an individual basis. But what we're seeing is we know that there are some key neurotransmitters and what a neurotransmitter is, is the body's chemical in the brain that helps us move messages around our brain. And there are two key neurotransmitters that we know are implicated within ADHD. So one of them is called dopamine and the other one is called noradrenaline. And we know both of those are what we might call dysregulated or different in the brain of people who have ADHD.

Chris - To what extent is this something that a person grows into? Because obviously we know the more we do something, the better our brains become at doing that thing. So is it that an environment pushes an individual to develop in a certain way and then they develop these traits that you are seeing behaviourally, but also on brain scans? And in fact, if they developed in a different environment, that wouldn't happen?

Jo - So the research tells us that people are born with their brains in this way. And, as much as our brains can be moldable and have some neuroplasticity to them so that they can change, actually we can't change them by doing more of something to make those neurotransmitters work differently. They do work differently. And the only way to support that change is possibly through medication or through learning different strategies to, get round or hijack some of the, the challenges that someone might have. So we might call them a toolbox or techniques that people use to adjust their life so that they can manage the difficulties in a different way. But you can't train the brain to not have ADHD

Chris - To what extent, though, is a person with ADHD a normal person, and what we've done is to medicalise an extreme of normality. Because if we think about the population as a range of different traits and personalities and behaviours and, and characteristics, and there are always extremes in a normal range. And some people might be at one end of that range. And are we not in danger of giving people a label when there isn't anything wrong with them, it's just the way they are?

Jo - I think that's a really important question and a really hot topic. Absolutely. And I think one of the things that's really important to remember about ADHD is that you need to go for an assessment with a qualified medical professional to be diagnosed with ADHD. And part of that process is to assess and understand the impact of the difficulties on somebody's life. So the impact on school, the impact on home or in the workplace, depending on where someone's at in their lifetime really. And there has to be a significant impact of their symptoms, of inattention, hyperactivity, and impulsivity on their daily living. And that's part of the criteria to meet the threshold for an ADHD diagnosis.