Predictors of an earlier diagnosis of Autism Spectrum Disorder in children and adolescents: a systematic review (1987-2017)

Autism Spectrum Disorder (ASD) is an early onset neurodevelopmental disorder in which the first signs generally emerge at approximately 12 months of age but its diagnosis is feasible only from the age of 18 months. According to the literature, the average age of diagnosis ranges from 2.7 to 7.2 years, which raises the question of factors associated with early diagnosis as a condition for early intervention. In this systematic review, we aim to identify clinical, social, and environmental factors associated with the age at which the diagnosis of ASD is confirmed in children. A literature search was performed in the Pubmed, Web of Sciences, PsycInfo, and Cochrane databases. Among the 530 publications identified, 50 were selected according to the inclusion criteria. This review focuses on studies conducted in 21 countries using data collected over a period from 1987 to 2017. These studies were published before December 31st, 2019. The results suggest that the diagnosis of ASD occurs earlier if there is a delay in social communication or the presence of intellectual disability. There is a low level of evidence concerning associations between the age at diagnosis and sex, race, parental education, or socioeconomic status and accessibility to health care. Further studies using large and well-characterized data sets are needed to simultaneously explore clinical and socio-environmental factors involved in early diagnosis.

COVID-19 phobia in a boy with undiagnosed autism spectrum disorder: A case report

RATIONALE

Coronavirus disease 2019 (COVID-19) is affecting mental health profoundly. Previous studies have reported pandemic-related anxiety. Anxiety disorder and autism spectrum disorder (ASD) are common comorbidities. However, there has been no report of any patient with undiagnosed ASD who developed anxiety disorders caused by the COVID-19 pandemic. In this case report, we describe an 8-year-old Japanese boy with undiagnosed ASD who developed COVID-19 phobia, resulting in avoidant restrictive food intake disorder (ARFID).

PATIENT CONCERNS

As COVID-19 was highly publicized in the mass media and the risk of droplet infection was emphasized upon, the patient began to fear viral contamination from food, culminating in a refusal to eat or even swallow his saliva. He was admitted to a pediatric medical center in Osaka with life-threatening dehydration and was then referred to our child psychiatry department.

DIAGNOSIS

We diagnosed the patient with COVID-19 phobia resulting in ARFID. We identified ASD traits from his present social communication skills and developmental history.

INTERVENTIONS

We provided psychoeducation of ASD for the parents and administered supportive psychotherapy.

OUTCOMES

Shortly after our intervention to relieve his ASD-related anxiety, his dysphagia improved.

LESSONS

Our findings suggest that children with undiagnosed ASD may develop COVID-19 phobia. In these cases, intervention for ASD may be more appropriate than starting treatment for anxiety disorders as the first-line option. COVID-19 is the biggest pandemic in the recent past, and more undiagnosed ASD patients who develop COVID-19 phobia may seek treatment. Clinicians should consider the underlying ASD in these patients and assess their developmental history and present social communication skills.

Factors Associated with a Delayed Autism Spectrum Disorder Diagnosis in Children Previously Assessed on Suspicion of Autism

This study aimed to investigate factors associated with a delayed autism spectrum (ASD) diagnosis when compared to children with either no or early ASD diagnosis. Among 893 children assessed for ASD before age 8, 39% had no ASD at baseline, of which 21% received a later ASD diagnosis. Autism symptoms, diagnostic history of other developmental disorders, cognitive ability, and socioeconomic factors were associated with delayed ASD. Autism Diagnostic Observation Schedule (ADOS) scores in delayed ASD fell between early and no ASD. Other developmental disorders, time and clinical trends like ADOS use and low parental education distinguished delayed and early ASD, whereas higher frequency of IQ < 70 at baseline and a diagnosis of emotional disorders during follow-up distinguished delayed and no ASD.

Sex Differences in Age of Diagnosis and First Concern among Children with Autism Spectrum Disorder

OBJECTIVE

Early identification of autism spectrum disorder (ASD) is an essential healthcare priority. Girls may be at risk for late diagnosis, although research is equivocal regarding how sex and other factors relate to ASD identification. The goals of the current investigation were to (1) identify how child sex, cognitive abilities, and demographic factors relate to age of first concern (AOC) and age of diagnosis (AOD), (2) evaluate trends in AOC/AOD over time, and (3) consider whether main effects of sex on AOC/AOD are moderated by cognitive abilities or time.

METHOD

Children (N = 365; 20% female; 85.6% identified as White) with ASD participated through the Province of Ontario Neurodevelopmental Disorders (POND) Network. Study records included AOD, date/timing of diagnosis (between 1996 and 2017), age of first parent concern, demographics, and standardized cognitive testing results (24.7% of children had IQ scores below standard scores of 70).

RESULTS

Average AOC occurred before 2 years of age whereas average AOD occurred after 5 years of age. Girls did not differ on AOC but had a later AOD than boys. Higher verbal IQ was associated with later AOD more strongly in girls than boys. Regarding time-related changes, average AOC and AOD increased across the study period, more strongly for girls.

CONCLUSIONS

Results support that sex is a key factor underlying delays in ASD identification and highlight the urgent need to improve diagnostic practices among girls. Limitations and implications for improving the diagnostic process are discussed.

Abbreviations: ASD=autism spectrum disorder; IQ=intelligence quotient; AOC=parental report of age of first concern; AOD=age of diagnosis.

Is Earlier Better? The Relationship between Age When Starting Early Intervention and Outcomes for Children with Autism Spectrum Disorder: A Selective Review

Although the conventional wisdom is that “earlier is better” when it comes to intervention for children with ASD, it is not clear what evidence exists to support this notion. This review examined a group of studies that addressed outcomes for young children with ASD who started early intervention at a range of ages. The review was selective by including only papers that examined the age of initiation of treatment as well as baseline cognitive, language, or adaptive level and, in addition, employed a method to control for the covariance between early ability level and age of beginning intervention. Fourteen studies were identified and then compared on methods and outcomes. The support for “earlier is better” was mixed, but it was clear that complex relationships among predictor variables need to be explored in order to understand the role of age of starting early intervention for later outcomes.

Determinants of an autism spectrum disorder diagnosis in childhood and adolescence: Evidence from the UK Millennium Cohort Study

This study aimed to identify determinants of a late autism spectrum disorder diagnosis, including diagnoses made 'very late' (i.e., in adolescence), using the Millennium Cohort Study, a nationally representative population-based cohort in the United Kingdom. Children diagnosed with autism spectrum disorder by age 14 (N = 581) were included and grouped by the parent-reported timing of diagnosis: before school (up to age 5), during primary school (age 5-11) and during secondary school (age 11-14). Predictors of diagnostic timing, at the child, family and school levels, were investigated using multinomial logistic regression. Most (79%) children with autism spectrum disorder were diagnosed after school entry, and 28% were not diagnosed until secondary school. Among those not diagnosed until secondary school, 75% had been identified at age 5 years by a parent and/or teacher as having socio-behavioural difficulties. Being diagnosed after starting school was predicted by living in poverty (adjusted relative risk ratio: primary = 1.90, 95% confidence interval: 1.03-3.53; secondary = 2.15, 1.05-4.42) and/or having no initial parental concerns (primary = 0.32, 0.15-0.70; secondary = 0.19, 0.09-0.43). Having typical-range intelligence also predicted diagnosis during secondary school. The result indicates that those without cognitive delays and poorer children were at risk of 'very late' (i.e. adolescent) diagnosis. Strategies to promote earlier identification, targeting age at primary school entry, could help those more likely to be diagnosed late.Lay abstractDespite policy emphasis on early identification, many children with autism spectrum disorder are diagnosed late, with some being diagnosed as late as in adolescence. However, evidence on what determines the timing of autism spectrum disorder diagnosis including children diagnosed in adolescence is lacking. Understanding these determinants, particularly in those diagnosed later than is ideal, can inform the development of effective strategies to improve earlier identification of autism spectrum disorder. This study used a nationally representative population-based cohort in the United Kingdom to explore child, family and school level predictors of timing of autism spectrum disorder diagnosis. In the United Kingdom, 79% of the children with autism spectrum disorder were diagnosed after entering primary school and 28% during secondary school. Among those not diagnosed until secondary school, 75% had shown social difficulties noticed by parents and/or teachers at age 5 years. The results suggest that healthcare providers should be aware that, even for universal systems of care, those living in poverty and having higher intelligence are most likely to miss out on a timely diagnosis. Strategies to promote earlier identification among school-aged children, including targeting primary school entry age (i.e. around age 5) and that encouraging referrals for a formal assessment at the first report of concerns over the child's social development may benefit those children who would otherwise be diagnosed later.

Piloting the Use of a Short Observation List for ASD-Symptoms in Day-Care: Challenges and Further Possibilities

Early symptoms of autism spectrum disorder (ASD) develop through the second year of life, making a stable ASD diagnosis possible around 24 months of age. However, in general, children with ASD are diagnosed later. In this study we explored the use of a short observation list to detect symptoms associated with ASD in children 12-24 months of age attending typical day-care centers. The results indicate that a short observation list used by day-care teachers does not reveal sufficient properties to be independently used in young children in day-care centers. Further studies should explore multiple and repeated measures for early detection of symptoms associated with ASD in typical day-care centers.