ADHD in Western Australia: An iatrogenic ‘epidemic’ cured by bureaucracy? Time to focus on the facts

A recent Viewpoint (Whitely, 2012) robustly describes an almost heroic good versus evil struggle in which Western Australia (WA) bureaucracy (including himself) managed to rein in ‘reckless’ doctors who were over-prescribing stimulant medications (dexamphetamine and methylphenidate) in ‘epidemic’ proportions to WA children (i.e. under 18) with attention deficit hyperactivity disorder (ADHD) for no good reason (the medications have dubious efficacy and are widely abused he purports).

The measured ‘coalface’ response from an internationally renowned ADHD researcher (Levy, 2012), in the same issue, was more reassuring about the appropriate use of stimulants to assist in the management of ADHD. I would like to contribute a WA-centric counterpoint from my role as a clinician, researcher (Paterson et al., 1999) and past government ADHD committee member.

First, a supposed WA child ADHD ‘epidemic’ from 1989 to 2003 is proposed, with a figure of 20,648 WA people being put on prescription stimulants in the year 2000 (with child estimates ranging from 14,454 to 18,583). This was sourced from a Government publication (Department of Health, 2002) but it was widely accepted that this figure was unreliable – it was inferred from dispensing data, there was likely to be double counting and it was not broken down into child/adult groups. The inception in August 2003 of the compulsory completion of Health Department notification forms for every ADHD patient started on stimulant medication provided, for the first time, excellent detailed prescribing analysis in an annual report, which is ongoing (Department of Health, 2004–2010). These reports are still unmatched by the rest of Australia, unfortunately, thus making interstate comparisons difficult. The first report data in 2004 showed that 1.56% of children in WA (6821) had received at least one prescription for stimulant medication, which was well below the expected prevalence rate for ADHD of 5–10% (The Royal Australasian College of Physicians, 2009).

It is debatable as to what proportion of those diagnosed with ADHD should then receive stimulants, but it is clear that at a 1.19–1.84% (range 2004–2010) prescribing rate, WA doctors were not prescribing greater than the reported prevalence rate of 5–10% and were therefore clearly not over prescribing, and may well have been under prescribing. Subsequent bureaucratic intervention suggests the latter with the setting up in 2009 of two new ADHD-specific public child clinics (adults with ADHD remain neglected with virtually no public sector treatment available in WA).

The second major point was that tighter bureaucratic controls over stimulant prescribing from 2003 onwards led to a continuing decline in prescribing rates in children. Certainly they did decline from 2004 to 2010 (1.56% to 1.19% – about 24%), but this decline was probably not due to any major bureaucratic change as the only new requirement was for doctors to fill out a notification form for all new ADHD patients who had been prescribed stimulant medication – they were not required to make any major changes to their practice as to who they did or did not treat, and how they treated them. What seems a more likely reason for the decline was the retirement of several clinicians active in the area of ADHD and also demands on child psychiatrists to move from treating children to treating more adult ADHD patients whose numbers increased over the same period by 69% (0.29–0.49%; below the expected prevalence of 3.4–4.4%). Prescriber variables were likely to have had a major impact on prescription rates (e.g. the top 10% of prescribers in 2010 treated 60% of the children and from 2003 to 2010 the number of prescribers who had 50 or more patients reduced from 34 down to 31).

The third major point was about drug abuse. Diversion of prescription stimulants has been reported ( Haynes et al., 2010; Miller and Lang, 2007) in WA students (12–17-year-olds) who had used stimulants not prescribed for them at least once over the last year, with the figure dropping from 5.5% (2005) to 4.1% (2008). This decline is encouraging but any diversion remains a worry. The decline may well be due to the increased prescription of long-acting stimulant preparations over the same period (Department of Health, 2004-2010), which keeps medications out of schools by virtue of being once-daily, before-school dosing.

It is suggested that a decline in illicit amphetamines (i.e. methamphetamine or non-prescribed dexamphetamine) from 2002 to 2008 is related to the decrease in prescription stimulants. There may be a link but illicit amphetamine abuse declined along with a general decline in all other illicit drugs surveyed, suggesting a common factor in operation (e.g. better public health and/or drug enforcement activities). The connection between ADHD and substance abuse is an area of active research with suggestions that untreated ADHD is a risk factor for the development of substance abuse (Wilens, 2011), and that treating ADHD with stimulant medication may either block this development or have little effect (Wilens et al., 2011); there is little evidence for stimulant treatment leading to increased substance abuse.

The final point is about the Raine Study (a longitudinal, large, cohort study involving 2868 children from birth, beginning in 1989). Some data were extracted from the overall study to look at ADHD, and some tentative suggestions were made (Department of Health, 2010). There are a number of significant limitations admitted by the authors, and their findings were not submitted to a peer-reviewed journal but publicised by the WA Health Department to encourage further research in the area. It is overstating the case to say that children are put at ‘risk of permanent cardiovascular damage’ based on these data. Much larger-scale studies, as discussed by Levy (2012), provide comfort to clinicians, suggesting that no more than routine assessment is warranted (with a possible screening electrocardiogram if suspicions are raised).

The Raine Study also questioned whether treating ADHD had significant long-term improvements in social, emotional and academic functioning. Longer-term studies over many years would be useful but, as in all areas of medicine, they are difficult to do. Research evidence seems to be lagging behind what clinical experience suggests (i.e. long-term ADHD treatment appears useful in both children and adults).

In summary: there is stronger evidence in WA for under rather than over prescribing of stimulants for children with ADHD (and adults for that matter); bureaucratic intervention has assisted with both ADHD research and improved clinical services; there is general awareness of the risks and benefits of stimulant medication; and there is widespread support for more research into the area, especially long-term outcomes.

See Viewpoint by Whitely, 2012, 46(5): 400-403. See also Viewpoint by Levy, 2012, 46(5): 404-406.