The US Government’s claims of an autism “epidemic” and their unscientifically-based claims of causes and triggers – including the use of paracetamol in pregnancy – are creating even more misunderstanding of the condition, and not helping those most affected by this very real issue, write Tara Eicher, John Quackenbush,and Ari Ne’eman in The New England Journal of Medicine.
In September last year, President Donald Trump and members of his administration released a series of statements on autism, attributing the condition to paracetamol use in pregnancy and to early-childhood vaccination.
The purported link between autism and vaccination has already been extensively debunked, and the literature suggesting an association between paracetamol and autism diagnosis does not support the causal claims being made by the White House.
A great deal has already been written about the scientifically dubious nature of these claims. But beyond these specific inaccuracies lies a larger misunderstanding of rising reported autism prevalence over the past several decades.
Although Trump and Secretary of Health and Human Services Robert F Kennedy Jr speak of an “autism epidemic”, the best available evidence suggests that the apparent increase in autism rates is predominantly attributable to shifting diagnostic practices, diagnostic substitution, broadened diagnostic criteria, increasing awareness, and the closing of diagnostic disparities based on race, socio-economic status, and probably sex.
Sixty-two years ago, Kennedy’s uncle, President John F Kennedy, gave a landmark speech about the condition then known as mental retardation and today referred to as intellectual disability.
He told the country that 3% of the population had an intellectual disability. The reduced prevalence of intellectual disability – currently estimated to be 1% to 2% – is not simply the result of improved public health and early-intervention practices.
Rather, it reflects a fundamental change in the boundaries of the diagnosis driven by an evolving understanding of developmental disability.
The definition of intellectual disability had been substantially expanded by the early-20th-century eugenics movement as a means to justify eugenicists’ broad campaign for forced sterilisation and institutionalisation.
As a more nuanced understanding of developmental disability developed, diagnostic practices changed as well, resulting in a shifting of children and adults who would previously have received a diagnosis of intellectual disability into other diagnostic categories, autism among them.
This shift has been well established as an important factor in the increase in autism diagnoses, with numerous studies documenting diagnostic substitution from both intellectual disability and other conditions, such as learning disability, using data from special education and long term services and supports.
The surge in autism diagnoses followed the codification of the diagnosis into the Diagnostic and Statistical Manual of Mental Disorders, third edition (DSM-III), in 1980 and its expansion in the DSM-IV in 1994.
Revisions that broadened the conception of autism were appropriate and largely in line with early understandings of the disability, which had encompassed a broad range of impairment.
The reduction of socio-economic, racial, and ethnic disparities in diagnosis most likely also plays an important role in rising autism rates, with the most recent incidence statistics from the Centres for Disease Control and Prevention (CDC) showing that disparities in access to diagnostic services have been substantially ameliorated according to the agency’s most recent study of eight-year-olds.
Improved diagnosis in women and girls may also have played a role.
These factors combined offer a far better explanation for the increase in autism rates over the past several decades than claims of an “epidemic”.
An imagined epidemic necessitates an imagined cause, which has led the administration to pursue questionable sources of environmental causation while ignoring other, well-established contributory factors.
Contrary to administration statements dismissing the role of genetics, the best available evidence suggests that autism is predominantly genetic in origin.
Autism is known to be one of the most highly heritable conditions and to be a complex polygenic condition linked to hundreds of genes, including both common and rare genetic variants.
Autistic people and their families have put forward important critiques of the current state of autism research, pointing out that genetic and other research on causation has crowded out other essential investments that could better support improved outcomes.
Of the $418m spent on autism research in 2020, only 8.4% focused on services and 4.3% on the needs of adults.
These figures reflect a serious failure of responsiveness to the priorities of the community that autism research dollars are meant to benefit.
Nevertheless, there is a role for research on genomics as a means of understanding the causal mechanisms of impairment in autism, in particular to support the development of interventions.
Justifiable ethical concerns have been raised regarding interventions that seek to force autistic persons to suppress beneficial or non-harmful autistic traits, such as hand-flapping or lack of eye contact.
Such interventions prioritise passing as non-autistic rather than more meaningful goals.
Yet interventions oriented toward such goals as communication, cognition and amelioration of intrinsically harmful traits (such as self-injury and seizures) are appropriate and necessary.
Disregarding such research in favour of ill-supported theories of environmental causation represents a severe error on the part of the federal government.
Research is best understood as a complement to a robust service system adequately financed to support the needs of autistic people or people with other developmental disabilities.
Unfortunately, recently passed cuts to Medicaid – which pays for the vast majority of autism and developmental disability services in America – have placed that service system, and the people who rely on it, at risk.
There is a sad irony in the administration’s claims that their autism agenda is oriented toward autistic persons with the most severe impairment. In truth, it is this population that stands to suffer the most from slashing the financing structure on which people with disabilities of all kinds depend for long-term services and supports, behavioural health services, and basic medical care.
The history of autism offers many reasons for fraught relationships between clinicians and autistic persons and their families. For decades, the psychiatric and especially psychoanalytic communities, relied on psychodynamic theories of the causation of autism that blamed “refrigerator mothers”.
It is thus unsurprising that a culture of distrust exists between parents of autistic children and physicians, a distrust that the President only exacerbates when he suggests that physicians are withholding information from families about environmental causes.
This rhetoric, specifically the blaming of mothers who use paracetamol during pregnancy for their children’s impairments, harkens back to past decades. Such rhetoric can cause concrete harms, encouraging expectant mothers to forgo essential treatment for fever and leading parents to turn to an exploitative alternative medicine industry peddling costly pseudoscience that frequently harms autistic people.
Autistic people and their families do deserve answers – not answers involving ill-conceived “causes” and pseudoscientific “cures”, but answers to their aspirations for improved services, medical care, and inclusion in society.
Much needs to be done to shift the focus of existing autism-research investments toward issues of immediate relevance to autistic people and their families.
Researchers who make this shift can help address the root causes of mistrust that make some parents of autistic people so receptive to pseudoscientific treatments and theories of causation.
Unfortunately, the direction the federal government is taking on autism seems calculated to exacerbate the divide.
Research programmes can be designed to maximise the benefits for autistic people and their families by studying both causes and the most effective and meaningful services and supports in an appropriate balance.
Such a constructive shift will not be accomplished, however, by alarmist claims about autism as an epidemic, chasing of ill-supported and debunked theories of causation, and further stigmatising autism.
Instead, it will require building strong, collaborative research programmes in which researchers from diverse fields join forces with autistic people and their families to generate lasting change.
Tara Eicher, Ph.D, John Quackenbush, Ph.D, and Ari Ne’eman, Ph.D – all from Harvard TH Chan School of Public Health
See more from MedicalBrief archives:
Brain changes in autism more sweeping than thought – UCLA study
Largest-ever study finds 102 genes responsible for autism
Major Lancet review debunks paracetamol, autism claims
US NIH to probe cause of autism