Parental report of vaccine receipt in children with autism spectrum disorder: Do rates differ by pattern of ASD onset?

Understanding Vaccine Hesitancy Among Parents of Children With Autism Spectrum Disorder and Parents of Children With Non-Autism Developmental Delays

Parents of children with autism spectrum disorder (ASD) may be at greater risk for developing antivaccine beliefs that lead to vaccine delays and/or refusals for their children. We investigated current parental vaccine hesitancy, parents' beliefs about causes of children's developmental delays, and children's vaccination histories among parents of children with ASD or non-ASD developmental delays. Data were analyzed from 89/511 parents (17.4%) who completed the Parent Attitudes About Childhood Vaccines questionnaire and the Revised Illness Perception Questionnaire; 46.1% had childhood vaccination records available. Overall, 21/89 (23.6%, 95% confidence interval [CI]: 15.0-34.0) of parents were vaccine hesitant (ASD n = 19/21 [90.5%], non-ASD n = 2/21 [9.5%]). Parents of children with ASD were significantly more likely to agree with "toxins in vaccines" as a cause of their child's developmental delays (28.4% vs 5.0%, P = .034). The odds of being vaccine hesitant were 11.9 times (95% CI 2.9-48.0) greater among parents who agreed versus disagreed that toxins in vaccines caused their children's developmental delays. Rates of prior vaccine receipt did not differ between hesitant and nonhesitant groups.

Vaccines and autism: a preliminary qualitative study on the beliefs of concerned mothers in Italy

Purpose: While a large body of evidence has shown that the administration of the measles-mumps-rubella (MMR) vaccine is not associated with an increased risk of autism spectrum disorder (ASD), a hesitant attitude towards childhood vaccination is still present among the public. In this study, we aim to investigate the mothers’ perceptions of the cause of their child’s ASD in order to increase our understanding of vaccine hesitancy.

Methods: This study draws on the analysis of 18 semi-structured interviews of mothers of children with ASD on the causes of autism.

Results: The interview material was content-analysed. The main themes were 1) childhood vaccines; 2) genetics; 3) specific conditions of the mother or the newborn at the moment of delivery; 4) environmental factors such as the mother’s lifestyle or her diet. The link between vaccines and autism was prevalent. About one third of the mothers reported that their child’s ASD was a consequence of a combination of two or more factors, i.e., childhood vaccines and specific conditions of the newborn or the mother at the moment of delivery.

Conclusion: This study provides preliminary insights into recurring sets of beliefs concerning the causes of ASD among the mothers of affected children.

Prevalence and Age of Onset of Regression in Children with Autism Spectrum Disorder: A Systematic Review and Meta-analytical Update

A systematic review published in 2013 reported 32% of children on the autism spectrum experience skill loss, known as autistic regression. However, the frequency varied depending on definition and measures used to capture skills. Retrospective parent report and prospective observation indicate loss of language and/or social skills, with motor skills typically unaffected. Our aim was to update the prevalence and age of onset of autistic regression through a meta-analysis of the literature to understand if there have been changes to the reported onset and prevalence since 2010. A systematic literature search was conducted using Medline, Embase, PsycINFO, and the Cochrane Library databases and included studies published from 2010 onward. Risk of bias assessment was performed on included studies. A random effects model was used to calculate the pooled prevalence and age of onset of autistic regression. Ninety-seven studies were included in the systematic review, of which 75 studies involving 33,014 participants had sufficient data for meta-analytic syntheses. The pooled proportion of autistic regression was 30% (95% confidence interval [CI]: 27-32%) but heterogeneity was high (I² = 96.91) and did not reduce with sensitivity or subgroup analyses based on study design or clinical differences, respectively. Prevalence varied according to risk of bias (low: 27%) and definition of regression (language: 20%, language/social: 40%, mixed: 30%, and unspecified: 27%). Weighted average age of onset was 19.8 months. Findings from this meta-analysis highlight the importance of developing a standardized definition of autistic regression, and tools to measure this at multiple time points during early childhood development. LAY SUMMARY: About a third of children with Autism Spectrum Disorder experience loss of skills, which is also known as autistic regression. This paper provides an update of the rate of autistic regression in children and the age when they first experience loss of skills, based on current studies. The findings from this review contribute to our understanding of the onset patterns of autistic regression. Unfortunately, studies are not sufficiently similar, making it difficult to provide clear answers on the exact timing or type of regression seen in different children.

Vaccine Hesitancy and Attributions for Autism among Racially and Ethnically Diverse Groups of Parents of Children with Autism Spectrum Disorder: A Pilot Study

Little is known about how racial/ethnic differences may influence attributions for autism spectrum disorder (ASD) and subsequent vaccine hesitancy, the latter of which refers to a continuum of concerns about vaccine safety that may lead to vaccine delays and/or refusals. Two hundred and twenty-five parents of children with ASD who were enrolled in the SPARK cohort (Simons Foundation Powering Autism Research for Knowledge) completed the Parent Attitudes about Childhood Vaccines survey and the Revised Illness Perception Questionnaire. 28.9% of respondents (n = 65) were vaccine hesitant (PACV score ≥ 50). Significant differences were observed between proportions of vaccine-hesitant parents (VHP) in the White sample and combined samples of color (Asian, Black, Latinx, Multiracial, and Other): 22.8% of the White sample (n = 39) versus 48.1% of the samples of color (n = 26). White, non-hesitant parents more often agreed with the child's brain structure as a cause of their child's ASD, while White, VHP more often agreed with the deterioration of the child's immunity as a cause. All VHP (regardless of race) agreed more often with diet, their own decisions, and vaccines as causes. VHP of color more often agreed with accident or injury, environmental pollution, their own general stress, and their own emotional state as causes. Future work should examine this phenomenon in larger, diverse samples to further understand differences across specific racial/ethnic groups. LAY SUMMARY: Some parents of children with autism spectrum disorder (ASD) are vaccine hesitant, meaning they have concerns about vaccine safety and may delay/refuse vaccines. We examined possible racial/ethnic differences related to how common vaccine hesitancy is and which causes of ASD were typically endorsed among a sample of caregivers in the SPARK cohort (Simons Foundation Powering Autism Research for Knowledge). Higher proportions of parents of color were vaccine hesitant, and all vaccine-hesitant parents agreed that "toxins in vaccines" were a cause of their child's ASD. Autism Res 2020, 13: 1790-1796. © 2020 International Society for Autism Research and Wiley Periodicals LLC.

A Conceptual Framework for Understanding the Cultural and Contextual Factors on Autism Across the Globe

Autism research is heavily skewed toward western high-income countries. Culturally appropriate screening and diagnostic instruments for autism are lacking in most low- and middle-income settings where the majority of the global autism population lives. To date, a clear overview of the possible cultural and contextual factors that may affect the process of identifying and diagnosing individuals with autism spectrum disorders (ASD) is missing. This study aims to outline these factors by proposing a conceptual framework. A multidisciplinary review approach was applied to inform the development of the conceptual framework, combining a systematic review of the relevant autism research literature with a wider literature search spanning key texts in global mental health, cultural psychiatry, cross-cultural psychology, and intellectual disability research. The resulting conceptual framework considers the identification, help-seeking, and diagnostic process at four interrelated levels: (a) the expression; (b) recognition; (c) interpretation; and (d) reporting of autism symptoms, and describes the cultural and contextual factors associated with each of these levels, including cultural norms of typical and atypical behavior, culture-specific approaches to parenting, mental health literacy, cultural beliefs, attitudes and stigma, as well as the affordability, availability, accessibility, and acceptability of services. This framework, mapping out the cultural and contextual factors that can affect the identification, help-seeking, and diagnosis of ASD may function as a springboard for the development of culturally appropriate autism screening and diagnostic instruments, and inform future cross-cultural autism research directions. The framework also has relevance for clinicians and policy makers aiming to improve support for underserved autism populations worldwide. Autism Res 2020, 13: 1029-1050. © 2020 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: The vast majority of autism research is conducted in western high-income settings. We therefore know relatively little of how culture and context can affect the identification, help-seeking, and diagnosis of autism across the globe. This study synthesizes what is known from the autism research literature and a broader literature and maps out how culture and context may affect (a) the expression, (b) recognition, (c) interpretation, and (d) reporting of autism symptoms.

Beliefs in vaccine as causes of autism among SPARK cohort caregivers

BACKGROUND

Fear of autism has led to a decline in childhood-immunization uptake and to a resurgence of preventable infectious diseases. Identifying characteristics of parents who believe in a causal role of vaccines for autism spectrum disorder (ASD) in their child may help targeting educational activities and improve adherence to the immunization schedule.

OBJECTIVES

To compare caregivers of children with ASD who agree or disagree that vaccines play an etiological role in autism for 1) socio-demographics characteristics and 2) developmental and clinical profiles of their children.

METHODS

Data from 16,525 participants with ASD under age 18 were obtained from SPARK, a national research cohort started in 2016. Caregivers completed questionnaires at registration that included questions on beliefs about the etiologic role of childhood immunizations and other factors in ASD. Data were available about family socio-demographic characteristics, first symptoms of autism, developmental regression, co-occurring psychiatric disorders, seizures, and current levels of functioning.

RESULTS

Participants with ASD were 80.4% male with a mean age of 8.1 years (SD = 4.1). Overall, 16.5% of caregivers endorsed immunizations as perceived causes of autism. Compared to caregivers who disagreed with vaccines as a cause for ASD, those who believed in vaccine causation came disproportionately from ethnic minority, less educated, and less wealthy backgrounds. More often their children had experienced developmental regression involving language and other skills, were diagnosed earlier, had lost skills during the second year of life, and had worse language, adaptive, and cognitive outcomes.

CONCLUSION

One in six caregivers who participate in a national research cohort believe that child immunizations could be a cause of autism in their child. Parent social background (non-White, less educated) and child developmental features (regression in second year, poorer language skills, and worse adaptive outcomes) index caregivers who are more likely to harbor these beliefs and could benefit from targeted educational activities.

Changing conceptualizations of regression: What prospective studies reveal about the onset of autism spectrum disorder

Until the last decade, studies of the timing of early symptom emergence in autism spectrum disorder (ASD) relied upon retrospective methods. Recent investigations, however, are raising significant questions about the accuracy and validity of such data. Questions about when and how behavioral signs of autism emerge may be better answered through prospective studies, in which infants are enrolled near birth and followed longitudinally until the age at which ASD can be confidently diagnosed or ruled out. This review summarizes the results of recent studies that utilized prospective methods to study infants at high risk of developing ASD due to family history. Collectively, prospective studies demonstrate that the onset of ASD involves declines in the rates of key social and communication behaviors during the first years of life for most children. This corpus of literature suggests that regressive onset patterns occur much more frequently than previously recognized and may be the rule rather than the exception.

Vaccination Patterns in Children After Autism Spectrum Disorder Diagnosis and in Their Younger Siblings

IMPORTANCE

In recent years, rates of vaccination have been declining. Whether this phenomenon disproportionately affects children with autism spectrum disorder (ASD) or their younger siblings is unknown.

OBJECTIVES

To investigate if children after receiving an ASD diagnosis obtain their remaining scheduled vaccines according to the Advisory Committee on Immunization Practices (ACIP) recommendations and to compare the vaccination patterns of younger siblings of children with ASD with the vaccination patterns of younger siblings of children without ASD.

DESIGN, SETTING, AND PARTICIPANTS

This investigation was a retrospective matched cohort study. The setting was 6 integrated health care delivery systems across the United States within the Vaccine Safety Datalink. Participants were children born between January 1, 1995, and September 30, 2010, and their younger siblings born between January 1, 1997, and September 30, 2014. The end of follow-up was September 30, 2015.

EXPOSURES

Recommended childhood vaccines between ages 1 month and 12 years.

MAIN OUTCOME AND MEASURE

The proportion of children who received all of their vaccine doses according to ACIP recommendations.

RESULTS

The study included 3729 children with ASD (676 [18.1%] female), 592 907 children without ASD, and their respective younger siblings. Among children without ASD, 250 193 (42.2%) were female. For vaccines recommended between ages 4 and 6 years, children with ASD were significantly less likely to be fully vaccinated compared with children without ASD (adjusted rate ratio, 0.87; 95% CI, 0.85-0.88). Within each age category, vaccination rates were significantly lower among younger siblings of children with ASD compared with younger siblings of children without ASD. The adjusted rate ratios varied from 0.86 for siblings younger than 1 year to 0.96 for those 11 to 12 years old. Parents who had a child with ASD were more likely to refuse at least 1 recommended vaccine for that child's younger sibling and to limit the number of vaccines administered during the younger sibling's first year of life.

CONCLUSIONS AND RELEVANCE

Children with ASD and their younger siblings were undervaccinated compared with the general population. The results of this study suggest that children with ASD and their younger siblings are at increased risk of vaccine-preventable diseases.

Reliability of parent recall of symptom onset and timing in autism spectrum disorder

Past events are often reported as occurring more recently than they actually took place, an error called forward telescoping. This study examined whether forward telescoping was evident in parent reports of autism spectrum disorder symptom emergence and onset classification. Parents were interviewed when their child was 2-3 years old (Time 1) and approximately 6 years old (Time 2). Significant forward telescoping was found in both age of social regression and age when language milestones were achieved, but not age of language regression. The correspondence between Time 1 and Time 2 onset report was low ( kappa = 0.38). Approximately one-quarter of the sample changed onset categories, most often due to parents not recalling a regression at Time 2 that they had reported at Time 1. These results challenge the use of retrospective methods in determining onset patterns.