Tuesday, 17 April 2012

ADHD (Attention-Deficit Hyperactivity Disorder)

ADHD: Please Pay Attention
(skip to the end for a bitesize summary)

‘ADHD is a condition that affects an individual’s ability to control attention and behaviour in an optimal and adaptive manner. It can cause individuals to become overactive and impulsive. The condition is frequently associated with educational underachievement, antisocial behaviour, and poor psychosocial adjustment.’ (Snowling and Hulme 2010). 

Attention-Deficit Hyperactivity Disorder is a story told in two parts: Hyperactivity/impulsivity (HI) and Inattention (IA). Individuals can be diagnosed with the predominantly HI or IA variety, but most are diagnosed with the combined type, hence AD+HD. More about the symptoms: NHS: symptoms of ADHD

ADHD is a hot topic. There are disagreements as to whether it is under- or over-diagnosed, and some even doubt its existence. Prevalence is in the range of 3-5% of UK school children and is more common in boys. Adults are also affected as the condition doesn’t diminish with age. 

Depending on your stance, it's caused either by: a deficit in executive functioning in the brain (control of inhibition and voluntary action thanks to dopamine and norepinephrine); an inability to defer gratification (called delay aversion), genes, or parenting styles.

Symptoms and diagnosis
  • To be diagnosed with ADHD, both symptoms of inattention and hyperactivity must be present in at least two different settings, e.g. at home and at school, for at least 6 months.
  • Clinicians are not required to observe children; rather, they rely on third-party accounts from teachers and parents, which surely plays a role in its misdiagnosis.

Adapted from Frederickson, N., Cline, T. (2009). Special Educational Needs, Inclusion and Diversity. London: OUP.

A lot of research has assessed commonly held beliefs that ADHD is under- or over-diagnosed. The latest[1] asked German psychiatrists to examine sample cases and give recommendations of diagnoses and treatment. Strikingly, the researchers found that gender played a role in likelihood of receiving a diagnosis of ADHD, with boys being more regularly misdiagnosed than girls because they fit the ‘prototypical criteria’ for the condition. These findings are pretty damning, although they are hardly comprehensive.  

Other research suggests that in fact global overdiagnosis is a myth. Sciutto and Eisenberg (2007)[2] found no justification for the claim that ADHD is overdiagnosed, pointing instead to public perceptions of the disorder.
Dr. Daniel Conner[3] offers some explanations of overdiagnosis:

·          Comorbidity (concomitant but unrelated conditions): as many as 75% of children diagnosed with ADHD also meet diagnostic criteria for other conditions like oppositional defiance disorder, depression, anxiety, and learning disorders. The trick is to tease out a set of symptoms specific to ADHD.

·          Inaccuracy: many clinicians are purported to use general rules of thumb and heuristics (trial-and-error methods) rather than relying on consistent diagnostic criteria. It seems that they rely on prototypical symptoms and characteristics, hence why boys are more likely to be diagnosed. 

·          Cognitive bias: this is an idea from social psychology whereby an individual actively seeks evidence that confirms his or her own theories and reasoning, “I’ve seen lots of kids with this condition, and you’re a lot like them, so you must also have it.”

·          Sex: as the German research shows, practitioners rely on prototypical criteria, which do not include girls. Girls are under-represented in this condition as they tend to display lower levels of disruptive behaviours, but are more likely to show inattention and social impairment.

In one study, children with late birthdays (making them younger than other classmates) were more likely to be diagnosed since their younger patterns of behaviour are misinterpreted. “We need to allow children to mature at different times and rates without pathologising these patterns”, says David Traxson[4]. He claims that DSM-5 will only exacerbate this problem.

Dr. Conner explains that before 1970 diagnosis of the condition was ~1%. Throughout the following decades the US government’s response to ADHD provided impetus for pharmaceuticals to begin feverish testing. In 2007, diagnosis rates were nearly 8%, but only 4.3% of these cases were prescribed medication. ADHD does not necessarily require medication, as there are plenty of other therapies available. Over-prescription is found in some regions, but it is certainly not a global problem. 

Does the rise from ~1% to 8% indicate overdiagnosis? Definitions of the disorder have changed since it was first described in 1902, with more focus being given to inattention by the 1980s. Broadening of the criteria necessarily includes more children in its scope, but does not represent overdiagnosis.

Recent findings[5] from Canada do indicate overdiagnosis and overmedication, suggesting that ADHD medications may be prescribed to deal with related conditions like oppositional defiance disorder (ODD) and conduct disorder. After all, criteria for these conditions are very similar.

Could there be a problem with the boundaries between these different disorders? If the same drugs work for ADHD, ODD, and conduct disorders, it is not possible that they are addressing the same problem, a common deficit running through each of them? It seems natural that kids with ODD who are argumentative, prone to tantrums, and are often angry and resentful would also be inattentive and hyperactive.

The legitimacy of ADHD as a disorder
So what’s the problem? Describing and explaining this disorder seems like pulling a square through a circular hole or struggling interminably to make a line of best fit. There are problems with its legitimacy in both public and scientific spheres, but I won’t go as far as Thomas Szasz in denying its existence, or indeed all other mental health disorders for that matter.

Social Construct Theory
A Social Constructionist explanation of mental illnesses or disorders is that they are not valid medical diagnoses, but rather excuses we have constructed in order to deal with socially unacceptable behaviour. Firstly, there are no robust neural correlates of ADHD. Secondly, comorbidity is extremely high (75%) which means that it can’t be considered a distinct disorder in its own right; it’s the leftovers of another disorder. And thirdly, ADHD is frequently associated with underachievement and poor psychosocial adjustment: The symptoms derive from these facts – how else would you expect poorly adjusted, low-IQ children to behave?

Our society has degraded to a point at which we can’t hold responsibility for this disgusting behaviour. There has been a ‘breakdown in the moral authority of adults’. The doctrine of ‘mother blame’ says that we use ADHD as a way of placing ultimate responsibility with the child’s primary attachment figure and their deficient child-rearing. Schools and teachers have lost grip and are not able to control children’s behaviour: a diagnosis of ADHD is a convenient way to relieve the burden on the classroom and the teacher. The pharmaceutical industry resides in shady corners, furtively offering Ritalin and Adderall to parents and clinicians seeking a quick fix.

In my opinion, what Social Construct Theory does is explain the views of the general public about the status of ADHD. What it doesn’t do is explain the disorder itself.

A Distinct Disorder
In fact, there are neural correlates of ADHD. It isn’t correct to emphasise dysfunction in any one region; the pattern is spread out, yet still distinctive[6]. Studies have consistently found patterns of frontal hypoactivity prefrontal cortices where executive function arises. There is strong evidence for the role of genes in development of ADHD. Research has also looked at endophenotypes – ways to inherit a tendency to develop ADHD which would be triggered by environmental or social factors. And actually, severe hyperactivity is a strong predictor of later psychosocial maladjustment rather than ADHD being the effect of it.

Dr. Connor puts it best:
“Doubt and confusion as to where this disorder fits into the general spectrum of illness further feeds the general perception that ADHD is a socially constructed disorder rather than a valid neurobiological disorder. This increases the public’s concern that ADHD is overdiagnosed and stimulants are overprescribed."

It appears that misdiagnosis is merely one part of the puzzle.

Attention-Deficit Hyperactivity Disorder is a slippery fish. To say that it (supposedly) affects so many people, it is poorly understood, and this is not helped by the general public’s acerbic criticism.
  • Is ADHD overdiagnosed? In some places, yes.

  • Why? It often occurs with other disorders that share symptoms, clinicians don’t tend to stick to strict rules, and they rely on prototypical criteria (like being male)

  • Is it overmedicated? Research suggests not, but ADHD medications may be used for related disorders, distorting the picture.

  • Some say that it isn’t a real disorder – explain. It’s seen as an excuse for slipping societal moral standards and bad parenting, which the pharmaceutical industry is cashing in on.

  • But some say it is a real disorder explain. Neurological studies have found distinctive patterns of brain function in people with the disorder, genes play a strong role, drugs have a significant effect in treating it, and it can predict later psychosocial maladjustment.

No comments:

Post a Comment