Response

No one was talking about ‘adult [attention-deficit hyperactivity disorder] ADHD’ 10 years ago, but Cortese et al write as if its status as a found object, a freestanding psychiatric category distinguishable from other categories, has been academically settled, and that it only remains to investigate questions such as its international prevalence. ^{Reference Cortese, Daley, Hollis, Rae, Ani and Asherson1} They assert that ‘[w]hen ADHD standardised diagnostic criteria are consistently applied, prevalence rates are generally consistent across countries’. This falls straight into the epistemological error that cultural psychiatrist Arthur Kleinman called a ‘category fallacy’: the assumption that because phenomena can be detected in various locations, they mean the same thing in all those locations. Moreover ‘ADHD standardised diagnostic criteria’ are not specific to ADHD but may contribute to other diagnoses – anxiety, depression, bipolar, personality disorder etc. – or perhaps more typically merely reflect longstanding stress-prone character traits. There is also marked regional and local variation in diagnosis rates, probably reflecting differing attitudes among clinicians and service factors. Moreover, the drive to diagnosis is self-reinforcing, as the perceived benefits in attention and concentration arise from the stimulant properties of amphetamines and are independent of an ADHD diagnosis. We must remember that the epistemological foundations of psychiatry are shallow: most psychiatric categories are not biologically validated diseases but merely symptom clusters we call syndromes, although the public are not reminded of this. No biological basis has been discovered for ‘neurodiversity’, nor for the statement on the National Health Service website that ‘the brain works differently’ with ADHD.

Cortese et al ignore the medicalisation of everyday life that has become a salient feature of modern society. Syndrome diagnoses via self-administered checklists are particularly susceptible to societal contagion and fashion – as we witness with ADHD in its spectacular extension from children to adults. Once something is declared real, it becomes real in its consequences. The epidemic to consider is not of ADHD but of ADHD prescribing, which means amphetamines. ^{Reference Summerfield2} Psychiatrists are being offered handsome fees to make one-off assessments of patients for whom the diagnosis of ADHD has basically been commissioned in advance, with amphetamines and referral to an overwhelmed National Health Service to follow. ADHD has become a multi-million-pound industry that is attractive to private equity because it offers a high-volume, low-risk business with high profit margins. ^{Reference Rowland3}

As it stands, the evidence base for ADHD treatment is not encouraging. Castells et al searched CENTRAL, MEDLINE, Embase, PsycINFO, ten other databases and two trials registers. They assessed these studies as of ‘low or very low quality’. ^{Reference Castells, Blanco-Silvente and Cunill4} They also noted death rates attributed to prescribed amphetamines. The umbrella review by Gosling et al noted that ‘no high certainty, long term evidence was found for any intervention’. ^{Reference Gosling, Garcia-Argibay, De Prisco, Arrondo, Ayrolles and Antoun5} In a meta-analysis, Ostinelli et al found that ADHD medications had no effect on longer-term outcomes such as quality of life. ^{Reference Ostinelli, Schulze, Zangani, Farhat, Tomlinson and Del Giovane6} Yet prescription rates are surging to astonishing levels. ^{Reference Wise7} Amphetamines have a long history as drugs of misuse, including associations with significant psychiatric complications and social decline. What will this amphetamine cohort be like in 10 years’ time?

In a telling intervention, Professor Allen Frances, the chairman of the DSM-IV task force, expressed regret for his role in the medicalisation of everyday human problems, such as overdiagnosis and overtreatment of the ‘worried well’. As examples, he cited what he called ‘false epidemics’ driven by their appearance in the DSM-IV: ADHD, autism and childhood bipolar disorder. In his seminal dissection of the health industry, Medical Nemesis (1975), Ivan Illich concluded that the more our lives were medicalised, the sicker we felt. ^{Reference Illich8} The seeming reluctance of psychiatry to be more public about the limitations of its knowledge claims may contribute to exacerbating and prolonging overmedicalisation, with the attendant costs that Allen Frances pointed to.