Friday, February 15, 2013

Beyond polemics: science and ethics of ADHD (critique by Yan Hong)

Attention-deficit hyperactivity disorder (ADHD) is one of the most common childhood psychiatric disorders in the world. Its main symptoms consist of inattention (be easily distracted, miss details, and frequently switch from one activity to another or have difficulty organizing and completing a task or learning something new or trouble completing homework assignments), hyperactivity and impulsiveness (fidget and squirm in their seats or talk nonstop or be very impatient)1. These symptoms emerge mainly before seven-year old and approximately 75% of those children are male2,3.

Two criteria are currently used to diagnose ADHD, Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) and International Classification of Diseases, 10th edition (ICD-10). American psychiatrists follow the DSM-IV, which describes two primary categories of behavioral symptoms: inattention and impulsivity-hyperactivity; and three subtypes of ADHD: inattentive type, hyperactive-impulsive type, and combined type. ICD-10, however, calls the condition Hyperkinetic Disorder (HKD or HD) and requires all three symptoms to be present for a diagnosis4,5. Despite the complexity of ADHD diagnosis, there are effective treatments for children. In the US and in Europe, psychostimulants are first-line treatments for the disorder. These drugs have been shown to be more effective on ADHD symptoms than behavioral therapy alone6. In the past decade rates of diagnosis have increased dramatically in most countries around the world. ADHD and its diagnosis and treatment have been considered controversial. The controversies involve teachers, parents, clinicians, social scientists, ethicists, regulator and children themselves.
Prevalence of ADD in the US as of 2007 (Source)

There are three positions in the debate. First, that ADHD is mainly caused by a combination of biological factors. From this perspective, diagnosis is valid and drug treatment is justified because it corrects an underlying neurochemical imbalance that affects cognitive and motor functions. Second, that ADHD is caused by a combination of biological and social factors; the diagnosis does not yet adequately capture the heterogeneity and complexity of the disorder. From this perspective, proponents accept the utility of stimulant drug medication; however, some proponents are skeptical of the widespread use of psychotropic drug treatment over other interventions, such as behavioral therapies. Third, that ADHD is a valid disorder but it is primary caused by environmental factors. This perspective views early recognition, prevention of exposure, and raising awareness about predisposing environmental factors in order to reduce dependence on stimulant medications7-10.

Diagnoses of ADHD are controversial because ADHD symptoms are difficult to distinguish from normal childhood behaviors. Also, stimulant drug treatment for children was long considered to be relatively safe11. Recently, more-serious side effects have led to new US food and Drug Administration warnings. Stimulant drugs are seen as potential threats to children’s right to this particular experience of childhood. As long as there is no indisputable scientific rationale for the growing rates of ADHD diagnosis and treatment in children, the validity of ADHD diagnosis and treatment will continue to be a controversial problem. This research aims to close interactions and collaborations between social scientists, ethicists, scientists and clinicians, because increasing scientific evidence suggests that ADHD cannot be explained by genetic or environmental factors alone. Social scientists and scientists can work together in two areas, and integrating social and scientific perspectives is likely to accomplish a more complete explanation.

--Yan Hong

Want to cite this post?

Hong, Y. (2012). Beyond polemics: science and ethics of ADHD (critique by Yan Hong). The Neuroethics Blog. Retrieved on , from

Works Cited

1. Remschmidt, H. & Global ADHD Working Group. Global consensus on ADHD/HKD. Eur. Child Adolesc. Psychiatry 14, 127–137 (2005).

2. Sax, L. & Kautz, K. J. Who first suggests the diagnosis of attention-deficit/hyperactivity disorder? Ann. Fam. Med. 1, 171–174 (2003).

3. Schneider, H. & Eisenberg, D. Who receives a diagnosis of attention-deficit/ hyperactivity disorder in the United States elementary school population? Pediatrics 117, e601–e609 (2006).

4. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (American Psychiatric Association, Washington DC, 2004).

5. World Health Organization. The ICD-10 Classification of Mental and Behavioral Disorders (World Health Organization, Geneva, 1992).

6. Jensen, P. et al. Findings from the NIMH Multi-modal Treatment Study (MTA): implications and applications for primary care providers. J. Dev. Behav. Pediatr. 22, 60–73 (2001).

7. Pelham, W. Psychosocial approaches to ADHD: what do we know about what works, and what does not? Presentation to the Hastings Centre NIH Working Group on Drugs in Pediatric Psychiatry (New York, 2007).

8. Linnet, K. M. et al. Maternal smoking during pregnancy risk of attention deficit hyperactivity disorder and associated behaviors: review of the current evidence. Am. J. Psychiatry 160, 1028–1040 (2003).

9. Braun, J. M., Kahn, R. S., Froehlich, T. Auinger, P. & Lanphear, B. P. Exposures to environmental toxicants and attention deficit hyperactivity disorder in U.S. children. Environ. Health Perspect. 114, 1904–1909 (2006).

10. McCann, D. et al. Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: a randomised, double-blinded, placebo-controlled trial. Lancet 370, 1560–1567 (2007).

11. Biederman, J. & Faraone, S. Attention deficit hyperactivity disorder. Lancet 366, 237–248 (2005).

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