Attention Deficit Hyperactivity Disorder (ADHD)

RESEARCH PROPOSAL

Attention Deficit Hyperactivity Disorder (ADHD): A study examining geographical variations in the diagnosis and treatment of ADHD across England over a period of one year.

Background and statement of the problem

Case for over-diagnosis All children exhibit the hallmark symptoms of impulsivity, hyperactivity and inattention to some degree; however, ADHD can only be positively diagnosed when these behaviours1,2 are expressed to an extreme or statistically rare extent together with clinical impairment in social, academic or occupational functioning.3 Treatment includes medical, social, psychological and behavioural interventions.

Despite these clear criteria, ADHD remains one of the most controversial psychiatric disorders due to its complicated diagnosis by differences in how rigorously the set of elements in the ICD-10 are applied.4 Other factors which affect the diagnosis of ADHD are the varying sources of information (parents, teachers or the patient) used to assess symptoms and whether the diagnosis is based on behaviour checklists, direct interviews or both.5,6

One study in 2004 revealed that eleven per cent of children were diagnosed with ADHD, albeit with no associated clinical impairments,7 which means that a high proportion of children were diagnosed incorrectly. With the lack of a biological marker,8 it may be argued that data exhibiting a prevalence exceeding four–eight per cent2 succinctly points to an issue of ADHD overdiagnosis.9 Variation in treatment across PCTs

In addition to the above, prescribing data in England and Wales10 over Quarter 4 of 2010 and Quarter 1 of 2011 reveals a variation of approximately 8,100 per cent in the total number of dispensed prescriptions for ADHD and 3,640 per cent in the net ingredient cost. Data for Quarter 4 of 2010 followed the same trend. his regional variation is likely to be influenced by several factors, such as demographic differences, including the number of secondary care assessment centres and the number of general practitioners (GPs) trained as ADHD specialists.

Abuse potential
Methylamphetamine has abuse potential similar to that of cocaine and d-amphetamine, and it is used to improve concentration and alertness, to get a “high” or for experimentation.11
Studies have shown that some patients are likely to “make up” the symptoms of ADHD to access stimulant drugs for abuse,12,13 either for personal use or for diversion to the illicit market.

Research question

Given the magnitude of the regional variation in the drugs prescribed and benefits and concerns about medication use, including side effects (disturbed appetite and sleep patterns, the high possibility of cardiovascular problems15 and inhibited growtstrong6), no study has been conducted that is methodologically rigorous to dismiss concerns about the overdiagnosis or overtreatment of ADHD or even abuse potential. better understanding of the issue will be obtained by considering ADHD prevalence on a primary care trust (PCT) basis.

This study aims to evaluate geographical variations in the diagnosis and treatment of ADHD among a nationally representative population of children under 18 years of age.

Study design

• Examination of Quality and Outcomes Framework databases for 2011 identifying the number of children under 18 years of age diagnosed with ADHD in 2011 as per the ICD-10 stratified on a PCT level
• Examination of NHS Information Centre (NHS IC) database for prescribed drugs in the category Central Nervous System drugs prescribed for ADHD stratified on a PCT level.

Variables such as sex, age, race, deprivation index, unemployment, population and others will also be taken into account.

Study population and sampling

Children under 18 years of age diagnosed as having ADHD across GP practices across England and Wales as per the ICD-10.

Data analysis methods

Data from the Quality and Outcomes Framework and prescribing databases held by NHS IC will be abstracted, tabulated systematically, and subjected to statistical analysis.

A multiple logistic regression model with random effects could be used to analyse simultaneously for the effect of age, gender, diagnostic tool and setting. This model accommodates the fact that each study estimated ADHD rates differently under slightly varying conditions.

How the data may be used

It is hoped that the data from this epidemiological study will help to inform public health policy for a specific segment of the population that cannot articulate its own needs.

REFERENCES

1. World Health Organisation. The ICD-10 Classification of Mental and Behavioural Disorders: Clinical Descriptions and Diagnostic Guidelines. Geneva, WHO, pp. 155–157.
2. Diagnostic and Statistical Manual of Mental Disorders IV (DSM IV).
3. National Institute of Clinical Excellence guidelines 72 (September 2008): Attention deficit hyperactivity disorder; Diagnosis and management of ADHD in children, young people and adults.
4. Foreman DM. (February 2006). Attention deficit hyperactivity disorder: legal and ethical aspects. Archives of Disease in Childhood 91 (2): 192–4. Sleator EK, Ullmann RK. (January 1981). Can the physician diagnose hyperactivity in the office? Pediatrics 67 (1): 13–7.
5. Baumgaertel A. Wolraich ML. Dietrich M. Comparison of diagnostic criteria for attention deficit disorders in a German elementary school sample. J Am Acad Child Adolesc Psychiatry. 1995; 34: 629–638.
6. Wolraich ML. Hannah JN. Pinnock TY. et al. Comparison of diagnostic criteria for attention-deficit hyperactivity disorder in a county-wide sample. J Am Acad Child Adolesc Psychiatry. 1996; 35: 319–324.
7. McArdle P. Prosser J. Kolvin I. (2004) Prevalence of psychiatric disorder: with and without psychosocial impairment. European Child and Adolescent Psychiatry, 13: 347–353.
8. Barkley RA, PhD. ADHD in Children: Diagnosis and Assessment.
9. Todd R. (2000). Genetics of attention deficit/hyperactivity disorder: Are we ready for molecular genetic studies? American Journal of Medical Genetics, 96(3), 241–243. Barkley R. (1999). Reflections on the NIH/NIMH Consensus Conference on ADHD. ADHD Report, 7(1): 1–4.
10. National Health Service Information centre – Data and Statistics.
11. Kollins SH, MacDonald EK, Rush CR (March 2001). Assessing the abuse potential of methylphenidate in nonhuman and human subjects: a review. Pharmacol Biochem Behav 68(3): 611–27. Newton PM. (July 3 2010). How easy is it to fake ADHD? Psychology Today. From Mouse to Man.
12. Sollman MJ. Ranseen JD. Berry DT. (2010). Detection of feigned ADHD in college students. Psychological Assessment 22(2): 325–335.
13. Wilens TE. Adler LA. Adams J. et al. (January 2008). Misuse and diversion of stimulants prescribed for ADHD: a systematic review of the literature. J Am Acad Child Adolesc Psychiatry 47(1): 21–31.
14. Cormier E. (October 2008). Attention deficit/hyperactivity disorder: a review and update. J Pediatr Nurs 23(5): 345–57.
15. Paykina N. Greenhill LL. (2007). Pharmacological treatments for attention-deficit/hyperactivity disorder; in A Guide to Treatments That Work. Edited by Nathan PE, Gorman JM. New York, Oxford University Press.
16. Swanson JM, Elliott GR, Greenhill LL. et al. (2007). Effects of stimulant medication on growth rates across 3 years in the MTA follow-up. J Am Acad Child Adolesc Psychiatry 46: 1015–27.