Autism in focus

Supporting people with autism requires a tailored approach focusing on individual strengths, needs, and preferences

Literature and cinema are no strangers to autism. One well known example is Barry Levinson’s film Rain Man (1988) starring Dustin Hoffman and Tom Cruise, respectively, as Raymond and Charlie Babbitt. The film, in which Hoffman portrays an autistic savant, was the highest grossing film of 1988 and the winner of four Academy Awards, including Best Picture and (for Hoffman) Best Actor. A more recent example is the ABC television series The Good Doctor, in which Freddie Highmore plays Dr Shaun Murphy, a gifted surgical resident with autism at a fictional hospital in California. A  literary example is Mark Haddon’s novel The Curious Incident of the Dog in the Night-Time, winner of the 2003 Whitbread Book of the Year Award and noteworthy for the narrative style of its autistic protagonist, who labels chapters only with prime numbers. All three cultural offerings are signs of a society willing to learn about autism.

Autism has had other, less fortunate, brushes with ‘fiction’.  In September 2025, US President Donald Trump attracted quite a bit of negative attention over his comments claiming there was a link between the widely-used painkiller Tylenol (paracetamol) and autism and that MMR vaccines should be taken separately rather than as a combined injection for the same reason. His remarks were vaguely reminiscent of claims by the British physician Andrew Wakefield, published in 1998 in a paper in the Lancet that was subsequently retracted. Wakefield, who was later found to have financial conflicts of interest and to have falsified his results, was removed by the General Medical Council from the medical register in 2010. Numerous subsequent studies have found no link between the MMR vaccine and autism. Similarly, Trump’s recent claims about paracetamol causing autism were met with widespread condemnation from a wide range of reputable medical sources, including the American College of Obstetricians and Gynaecologists.

In his comments, Trump, flanked by his Health Secretary Robert F Kennedy Jr, described autism diagnoses in the US increasing dramatically over the past two decades. He stated that the incidence of autism has increased from “one in 10,000… probably 18 years ago” to one in 31 by 2025. The more recent statistic is reasonably accurate, based on 2022 data from the US Centers for Disease Control and Prevention (CDC) in 2022.¹ This certainly represents an increase in autism diagnosis compared to 18 years ago. However, the 2007 figure of one in 10,000 cited by Trump is a marked underestimate. In fact, the CDC did not report a figure for 2007, but they did calculate the incidence of autism in the US to be around one in 111 in 2006 and one in 88 in 2008.² As such, the rise in autism is not nearly as dramatic as Trump has claimed. Moreover, rather than painkillers or vaccines, this increase is due mostly to a broadening of the autism diagnostic criteria and a greater public acceptance of its ubiquity.

Diagnostic criteria

So, what are the diagnostic criteria of what is still technically referred to as autism spectrum disorder (ASD)? The gold standard for diagnosis of ASD is through an Autism Diagnostic Observation Schedule (ADOS-2) assessment, which uses the criteria of the American Psychiatric Association’s Diagnostic and Statistical Manual (DSM-5).³ Notably, the DSM-5 criteria are very similar to those of the World Health Organisation’s International Classification of Diseases (ICD-11), the only significant difference being that the latter does not have severity levels as qualifiers. In the DSM-5, ASD is classified under neurodevelopmental disorders, a category that also includes intellectual disabilities, communication disorders, attention deficit/hyperactivity disorder, specific learning disorders, and motor disorders.

There are five diagnostic criteria for ASD described as A through E. A and B describe the symptoms, while C through E are qualifiers. The DSM-5 also describes three levels of severity, based on the amount of support needed ranging from “requiring support” to “requiring very substantial support”. Criterion A relates to persistent deficits in social communication such as difficulties with social reciprocity, initiating discussion, back-and-forth conversations, sharing of interests or emotions, and non-verbal communication (for example, body language, appropriate eye contact, gestures and facial expressions). Criterion A also describes challenges in adjusting behaviour to social contexts, making friends or sharing imaginative play, which can in turn lead to a difficulty maintaining and understanding relationships. Criterion B relates to restricted and repetitive patterns of behaviour, interests, or activities. This can include: Stereotyped or repetitive speech, movements or use of objects (colloquially known as stimming); ritualised patterns of behaviour and inflexible adherence to routines (typically presenting as significant distress when change is proposed); highly restricted interests with marked intensity; and hyper- or hypo-reactivity to sensory aspects of the environment. 

Criterion C states that these symptoms must be present in the early developmental period, although it is acknowledged that they may not present until social demands exceed an individual’s attenuated capacities and may be less prominent due to learnt strategies in later life (colloquially known as masking). Such compensation strategies can be a source of anxiety – and indeed exhaustion – because the individual with autism must consciously calculate what is socially intuitive for most people. This is sometimes referred to as autistic burnout. However, the DSM-5 acknowledges that a detailed developmental history may be difficult to obtain for an adult diagnosis of autism. In such cases, provided the clinical observations suggest the criteria are met and there is little or no developmental evidence of good social and communication skills, an autism diagnosis can be considered. Criterion D cites the need for a clinically-significant impairment in social, occupational, or other important areas of functioning. Criterion E exists to ensure that the symptoms are not better explained by intellectual disability, albeit noting that autism and intellectual disability often co-occur. 

Notwithstanding these criteria, there are many who are uncomfortable with the word ‘disorder’ at all. The language used in the medical model (the DSM-5 and ICD-11) tends to focus on ‘deficits’ and low versus high functioning, which can sometimes undermine the positive and meaningful aspects of a neurodiverse perspective in an individual’s life. Moreover, it appears to place all the responsibility on the individual to adapt to society and none on society to adapt to the individual. Instead, many people living with autism, along with their advocates, would argue in favour of a neuro-affirmative approach, as described below.⁴

Aetiology

As for the aetiology of autism, the prevailing reputable opinion involves a complex interaction of genetic and environmental factors. Twin studies show that if one twin has autism, the likelihood the other will is around 60 per cent. Environmental factors associated with autism include the use of thalidomide or valproate shortly before conception or during the early part of pregnancy.⁵ Premature and underweight birth are among the correlational factors. Of note, the mean age of autism diagnosis is four years, but diagnosis in adulthood is not uncommon.

Autism is not an Axis I psychiatric illness. However, it is important that clinicians be on the lookout for illnesses and co-morbidities that are commoner in people with autism. Around 70 per cent of people with autism have at least one other co-morbid diagnosis, while 40 per cent have at least two. According to Khachadourian and colleagues, 35.3 per cent of people with autism have ADHD, while 23.5 per cent have a learning disability, 21.7 per cent have intellectual disability, 21 per cent have sleep disorders, 19 per cent have social communication disorders, and 17 per cent have anxiety disorders.⁶ 

There is also significant overlap between autism and illnesses such as psychosis and bipolar disorder. A systematic review and meta-analysis published by Varcin and colleagues examined 53 studies and found the pooled prevalence of psychosis and bipolar disorder in adults with autism to be 9.4 and 7.5 per cent, respectively.⁷ This is considerably higher than the baseline prevalence of either illness in the general population. However, the authors also cited a dearth of research examining risk factors for these Axis I disorders in autism. In other words, they could not say for certain why people with autism are more prone to psychosis or bipolar disorder, although they observed that men with autism had a higher risk of psychosis and women with autism had a higher risk of bipolar disorder. The need for ongoing assessment and monitoring was highlighted.

An interesting paper by Gesi and colleagues in the Journal of Psychiatric Research also highlighted the increased rate of psychosis in people with autism.⁸ Noting the increase in autism prevalence in recent decades, ‘owing to the diagnostic accretion of low-impairment forms, over and above other possible causes’, as they put it, they remarked that unrecognised autism can sometimes be mislabelled as psychosis, while in other cases psychotic disorders can sometimes be overlooked in people with autism in a process known as diagnostic overshadowing. The authors referred to three meta-analyses on psychosis in the context of people with autism and concluded that it is at least 10-times higher than in the general population. The authors highlighted a concerning paucity of literature on risk factors, outcomes, and treatment options for this specific cohort of patients.

Neuro-affirmative approach

So, what might a neuro-affirmative approach involve? Supporting people with autism requires a tailored approach based on individual strengths, needs, and preferences rather than assuming ‘one-size-fits-all’. Firstly, clear communication is key, utilising concrete language and avoiding abstract or ambiguous terminology. Individuals with autism also need time to process what you are saying and formulate a response. Some services suggest a ‘10 second rule’ after asking a question or making a comment. Similarly, anxiety can be reduced by clear and predictable routines with structured timelines that allow the individual with autism to anticipate what will happen. Give fair warning about changes to environment or activity. Written information or the use of visual aids like photographs or videos may help.

Secondly, support should be individualised, focusing on strengths, unique talents, passions, and interests to nurture confidence and self-esteem. It is also important to be aware of sensory needs and processing differences, and to provide environments that support sensory regulation. AsIAm offer advice to organisations (including clinics and surgeries, for example) on the creation of autism-friendly spaces. On an individual level, strategies might include a quiet room in the house, a walk in the woods, noise-blocking headphones, and so forth. It helps to be well informed on what the individual tends to like, dislike and worry about, and to offer them some control over their daily activities and provide a general sense of empowerment. Try to be flexible.

This leads us to the third ‘principle’, if you like, which is collaboration. It is not just about involvement in decisions regarding daily activities, but overall respect for autonomy and ensuring that individuals with autism are central to all decisions about their support and intervention. Modelling calm and appropriate behaviour may help with this. Collaboration with family and other professionals will help to develop a comprehensive support system in which the individual is central. Finally, interventions should always be evidence-based.

On 18 December 2007, the United Nations General Assembly adopted a resolution marking 2 April each year as World Autism Awareness Day.⁹ According to the Department of Health, the prevalence of autism in the Irish population is around 1.5 per cent. However, in 2022 the National Council for Special Education examined their data, validating research which reported the prevalence of autism to be 3.38 per cent in Ireland, and not the previously reported rate of 1.55 per cent in 2018.¹⁰ The male to female ratio for the diagnosis of autism is 4:1, although this figure is sometimes contested because females are typically diagnosed later in life, while diagnostic tools are traditionally standardised for male cohorts.¹¹ A Northern Irish report published in 2025 found the prevalence of autism among school-aged children there to be 5.9 per cent (3.4 per cent of females and 8.3 per cent of males), only 18 per cent of whom had no special educational needs.¹² The prevalence was 38 per cent higher in the most deprived 10 per cent of the population compared to the Northern Ireland average. So, is there any reason to think that these statistics are different in the Republic?    

A couple of years back, the Journal.ie published an investigative piece which described children waiting years for autism assessments, leading to developmental delays and lack of access to essential educational supports and school places.¹³ According to a 2021 survey by AsIAm, 42 per cent of respondents were waiting more than two years for assessment.¹⁴

In the end, unhelpful and inaccurate claims by the Trump administration will always garner headlines and generate public debate. But behind the smoke screen lies the more serious challenge of society adapting to provide meaningful support to people with autism, particularly those at greater risk of developing Axis I mental illness. Nothing less is acceptable in an inclusive and compassionate society. 

References

1. Centers for Disease Control and Prevention (CDC). Prevalence and Characteristics of Autism Spectrum Disorder Among Children Aged 8 Years — Autism and Developmental Disabilities Monitoring Network, 11 Sites, United States, 2020. MMWR Surveill Summ [In- ternet]. 2025 [cited 2025 Oct 12];74(2). Available at: www.cdc.gov/ mmwr/volumes/74/ss/ss7402a1.htm?s_cid=ss7402a1_w

2. Centers for Disease Control and Prevention (CDC). Autism Data Vis- ualisation Tool [Internet]. 2025 [cited 2025 Oct 12]. Available at: www. cdc.gov/autism/data-research/autism-data-visualization-tool.html

3. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 5th ed. Washington, DC: APA; 2013

4. Chellappa SL. Neuroaffirming services for autistic people. Lancet Psychiatry. 2024;11(2):96–7

5. Ostrowski J, Religioni U, Gellert B, et al. Autism spectrum disor- ders: Etiology, epidemiology, and challenges for public health. Int Med J Exp Clin Res. 2024;30:e944161

6. Khachadourian V, Mahjani B, Sandin S, et al. Comorbidities in autism spectrum disorders and their etiologies. Transl Psychiatry. 2023;13(1):71

7. Varcin KJ, Herniman SE, Lin A, et al. Occurrence of psychosis and bipolar disorder in adults with autism: A systematic review and me- ta-analysis. Neurosci Biobehav Rev. 2022;134:104543

8. Gesi C, Giacovelli L, Reibman YL, et al. Beyond imagination: Sorting out and treating psychosis in the context of autism spectrum disorder. J Psychiatr Res. 2024;173:363–6

9. United Nations. World Autism Awareness Day [Internet]. 2025 [cited 2025 Oct 12]. Available at: www.un.org/en/observances/autism-day

10. National Council for Special Education (NCSE). An Inclusive Education for an Inclusive Society: Policy Advice Paper No. 7 [Internet]. 2024 [cited 2025 Oct 12]. Available at: https://ncse.ie/wp-content/ uploads/2024/05/An_Inclusive_Education_for_an_Inclusive_Socie- ty_NCSE_Policy_Advice_Paper_7.pdf

11. Napolitano A, Schiavi S, La Rosa P, et al. Sex differences in au- tism spectrum disorder: Diagnostic, neurobiological, and behaviour- al features. Front Psychiatry. 2022;13:889636

12. Department of Health (Northern Ireland). Prevalence of Autism in School-Age Children in Northern Ireland 2025 [Internet]. Belfast: Department of Health; 2025 [cited 2025 Oct 12]. Available at: www.health-ni.gov.uk/sites/default/files/2025-05/autism-chil- dren-ni-2025.pdf

13. TheJournal.ie. Assessing autism: Calls for improved access to diagnosis and supports in Ireland [Internet]. 2023 Mar [cited 2025 Oct 12]. Available at: www.thejournal.ie/assessing-au- tism-6019877-Mar2023/

14. AsIAm. Ireland’s National Autism Charity [Internet]. 2025 [cited 2025 Oct 12]. Available at: https://asiam.ie/

Dr Arunava Guha, Registrar in Psychiatry, St John of God University Hospital, Dublin, and Dr Stephen McWilliams, Clinical Associate Professor of Psychiatry, School of Medicine, University College Dublin, Honorary Clinical Senior Lecturer, RCSI University of Medicine and Health Sciences, and Consultant Psychiatrist, St John of God University Hospital, Dublin