Lonnie Zwaigenbaum

• MSc MD
• Professor at University of Alberta

Background: Mental health problems are elevated in autistic individuals but there is limited evidence on the developmental course of problems across childhood. We compare the level and growth of anxious-depressed, behavioral and attention problems in an autistic and typically developing (TD) cohort. Methods: Latent growth curve models were appli...

Background Canonical babbling—producing syllables with a mature consonant, full vowel, and smooth transition—is an important developmental milestone that typically occurs in the first year of life. Some studies indicate delayed or reduced canonical babbling in infants at high familial likelihood for autism spectrum disorder (ASD) or who later recei...

We examined the relations of restricted and repetitive behaviors (RRB; insistence on sameness, repetitive sensory-motor, self-injurious behavior) to social skills overall and aspects that comprise social skills as measured by the VABS-II (coping skills, play/leisure time, interpersonal relationships) in 24- (n = 63) and 36-month old (n = 35), high-...

Background Restricted and repetitive behavior (RRB) is one of the characteristic features of Autism Spectrum Disorder. This domain of symptoms includes a broad range of behaviors. There is a need to study each behavior individually to better understand the role of each in the development of autistic children. Moreover, there are currently no longit...

Identification of genetic biomarkers associated with autism spectrum disorders (ASDs) could improve recurrence prediction for families with a child with ASD. Here, we describe clinical microarray findings for 253 longitudinally phenotyped ASD families from the Baby Siblings Research Consortium (BSRC), encompassing 288 infant siblings. By age 3, 103...

Preschool children with autism spectrum disorder (ASD) experience slower development of daily living skills (DLS) that are essential for independent functioning compared to typically developing children. Few studies have examined the trajectories of DLS in preschoolers with ASD and the existing literature has reported conflicting results. This stud...

Background: Language delay is extremely common in children with autism spectrum disorder (ASD), yet it is unclear whether measurable variation in early language is associated with genetic liability for ASD. Assessment of language development in unaffected siblings of children with ASD can inform whether decreased early language ability aggregates...

Early communication impairment is among the most-reported first concerns in parents of young children with autism spectrum disorder (ASD). Using a parent-report questionnaire, we derived trajectory groups for early language and gesture acquisition in siblings at high risk for ASD and in children at low risk, during their first 2 years of life. Deve...

Initiation of joint attention is a critical developmental function related to further social communicative development in infancy.Joint attention appears to be impaired very early in life for children with autism spectrum disorder (ASD), well before a formaldiagnosis is established. To observe the early development of joint attention, we prospectiv...

Preschool-aged siblings of children with ASD are at high-risk (HR) for ASD and related challenges, but little is known about their emerging peer competence and friendships. Parents are the main providers of peer-relationship opportunities during preschool. Understanding parental challenges supporting early peer relationships is needed for optimal p...

The purpose of the current study was to examine how repetitive behaviour in Autism Spectrum Disorder (ASD) is related to intrinsic functional connectivity patterns in a number of large-scale, neural networks. Resting-state fMRI scans from thirty subjects with ASD and thirty-two age-matched, typically developing control subjects were analysed. Seed-...

Although anxiety is frequently reported in children with autism spectrum disorder (ASD), existing anxiety scales are often psychometrically inappropriate for this population. This study examined the internal structure, reliability, convergent and discriminant validity of the Spence Children’s Anxiety Scale-Parent Report (SCAS-P; Spence 1999) in 238...

Resting state functional magnetic resonance imaging (rs-fMRI) in infants enables important studies of functional brain organization early in human development. However, rs-fMRI in infants has universally been obtained during sleep to reduce participant motion artifact, raising the question of whether differences in functional organization between a...

Background & aims In response to limited research on early language development in infants at high risk for Autism Spectrum Disorder (ASD), the current prospective study examined early expressive and receptive language trajectories in familial high-risk (HR) infants who were and were not later diagnosed with ASD (HR-ASD and HR-N, respectively), and...

Introduction: We provide data on visual orienting and emotional distress in infants at high and low risk for autism spectrum disorder (ASD). Method: Participants included 83 high-risk (HR) infants with an older sibling with ASD and 53 low-risk (LR) control infants with no family history of ASD. Infants were assessed on the gap-overlap task and a...

Purpose Impairments in the social use of language are universal in autism spectrum disorder (ASD), but few standardized measures evaluate communication skills above the level of individual words or sentences. This study evaluated the Expression, Reception, and Recall of Narrative Instrument (ERRNI; Bishop, 2004) to determine its contribution to ass...

Background: Younger siblings of children with autism spectrum disorder (ASD) are themselves at increased risk for ASD and other developmental concerns. It is unclear if infants who display developmental concerns, but are unaffected by ASD, share similar or dissimilar behavioral and brain phenotypes to infants with ASD. Most individuals with ASD exh...

The employment rate among persons with autism spectrum disorder has been noted as unacceptably low. Employment-support services are increasingly linked to the potential for favorable job outcomes, yet little is known about employment-support practices and the outcome of these interventions. This mixed-methods study examined employment-support resou...

To evaluate the efficacy of the Social ABCs parent‐mediated intervention for toddlers with suspected or confirmed autism spectrum disorder (ASD), through a cross‐site randomized control trial, sixty‐three parent–toddler dyads (toddler age: 16–30 months) were randomized into treatment ( Social ABCs ) or control (service‐as‐usual) conditions. Video d...

The purpose of this scoping review was to identify participation measures for preschool children with autism spectrum disorder (ASD). A comprehensive search strategy was employed across several electronic databases with hand searching of reference lists. Seven measures of participation were identified; five measures had standardization samples that...

Prevalence of self-injurious behavior (SIB) is as high as 50% among children with autism spectrum disorder (ASD). Identification of risk factors for the development of SIB is critical to early intervention and prevention. However, there is little empirical research utilizing a prospective design to identify early risk factors for SIB. The purpose o...

Background: We previously reported that infants who developed ASD had increased CSF in the subarachnoid space (i.e., extra-axial CSF) from 6-24 months of age (Shen et al., 2013; Brain). We attempt to confirm and extend this finding in a larger, independent sample. Methods: A longitudinal MRI study of infants at-risk for ASD was carried out on 343...

We are performing whole-genome sequencing of families with autism spectrum disorder (ASD) to build a resource (MSSNG) for subcategorizing the phenotypes and underlying genetic factors involved. Here we report sequencing of 5,205 samples from families with ASD, accompanied by clinical information, creating a database accessible on a cloud platform a...

Background Restricted and repetitive behaviors are defining features of autism spectrum disorder (ASD). Under revised diagnostic criteria for ASD, this behavioral domain now includes atypical responses to sensory stimuli. To date, little is known about the neural circuitry underlying these features of ASD early in life. Methods Longitudinal diffusi...

Children's early language environments are related to later development. Little is known about this association in siblings of children with autism spectrum disorder (ASD), who often experience language delays or have ASD. Fifty-nine 9-month-old infants at high or low familial risk for ASD contributed full-day in-home language recordings. High-risk...

Background: Autism spectrum disorder (ASD) is a developmental disorder defined by behavioral features that emerge during the first years of life. Research indicates that abnormalities in brain connectivity are associated with these behavioral features. However, the inclusion of individuals past the age of onset of the defining behaviors complicate...

Prader-Willi syndrome (PWS), a rare genetic disorder caused by the lack of expression of paternal genes from chromosome 15q11-13, has been investigated for autism spectrum disorder (ASD) symptomatology in various studies. However, previous findings have been variable, and no studies investigating ASD symptomatology in PWS have exclusively studied c...

This report originated from discussions at the Annual Brain Development Conference in late 2013 between researchers in the Neuroethics Core and Autism Spectrum Disorders Project of NeuroDevNet. Discussants felt that return of research results is a pertinent issue but that researchers are missing a comprehensive picture of the recommendations, appro...

Prospective studies of infant siblings of children diagnosed with autism spectrum disorder (ASD) provide a unique opportunity to characterize ASD as it unfolds. A critical question that remains unanswered is whether and how these children with ASD resemble other children identified from the community, including those with no family history. The pur...

Brain enlargement has been observed in children with autism spectrum disorder (ASD), but the timing of this phenomenon, and the relationship between ASD and the appearance of behavioural symptoms, are unknown. Retrospective head circumference and longitudinal brain volume studies of two-year olds followed up at four years of age have provided evide...

Initiating joint attention (IJA), the behavioral instigation of coordinated focus of 2 people on an object, emerges over the first 2 years of life and supports social-communicative functioning related to the healthy development of aspects of language, empathy, and theory of mind. Deficits in IJA provide strong early indicators for autism spectrum d...

The goal of this chapter is to discuss the concept of “resilience” against the background of the remarkable heterogeneity seen in the natural history of autism spectrum disorder (ASD). Classically, resilience refers to the occurrence of an unexpected “good outcome” in the face of adversity. In this chapter, adversity is the diagnosis of ASD and res...

This study examined whether a novel parent-report questionnaire, the Autism Parent Screen for Infants, could differentiate infants subsequently diagnosed with autism spectrum disorder from a high-risk cohort (siblings of children diagnosed with autism spectrum disorder (n = 66)) from high-risk and low-risk comparison infants (no family history of a...

Research related to supports for adults with autism spectrum disorder (ASD) is under-developed. As an example, system and service development to support successful transition to adulthood and meaningful vocation for adults has received relatively little research scrutiny until recently, with practitioners and program developers lacking evidence-inf...

Appendix S1. The ASD expert survey

De novo mutations (DNMs) are important in autism spectrum disorder (ASD), but so far analyses have mainly been on the ~1.5% of the genome encoding genes. Here, we performed whole-genome sequencing (WGS) of 200 ASD parent–child trios and characterised germline and somatic DNMs. We confirmed that the majority of germline DNMs (75.6%) originated from...

This study characterized developmental outcomes of a large sample of siblings at familial high-risk of autism spectrum disorder (ASD), who themselves did not have ASD (n = 859), and low-risk controls with no family history of ASD (n = 473). We characterized outcomes at age 3 years using a developmental assessment of language and learning and an obs...

Care for children with autism spectrum disorder (ASD) in the emergency department (ED) is increasingly recognized as difficult. Communication, sensory and behavioral challenges in a high intensity environment pose risks for negative experiences and outcomes. Through semi-structured interviews, parents (n = 31) and their children (n = 4) with ASD sh...

Messinger et al. found a 3.18 odds ratio of male to female ASD recurrence in 1241 prospectively followed high-risk (HR) siblings. Among high-risk siblings (with and without ASD), as well as among 583 low-risk controls, girls exhibited higher performance on the Mullen Scales of Early Learning, as well as lower restricted and repetitive behavior seve...

This study aimed to characterize the perspectives of health professionals who care for children with autism spectrum disorder (ASD) in the emergency department (ED) and to determine what strategies could optimize care. Ten physicians and twelve nurses were interviewed individually. Questions related to experiences, processes, clinical decision-maki...

Aim: Impairments in social communication are the hallmark of autism spectrum disorder (ASD). Operationalizing 'severity' in ASD has been challenging; thus, stratifying by functioning has not been possible. The purpose of this study is to describe the development of the Autism Classification System of Functioning: Social Communication (ACSF:SC) and...

This study examined the longitudinal associations between child behavior problems, coping strategies, social resources, and parenting stress in mothers of young children with autism spectrum disorder. Participants were 283 mothers who completed self- and child-report measures at the time of diagnosis and 2 years later. Hierarchical multiple regress...

The co-occurring development of internalizing and externalizing problems were examined in an inception cohort of 392 children diagnosed with autism spectrum disorder at age 3 who were assessed on four occasions. Results indicated that internalizing and externalizing problems were stable over time and highly comorbid. Joint trajectory analysis sugge...

Children and youth with autism spectrum disorder presenting in emergency departments face potential cognitive, sensory, and behavioral challenges, and it is crucial for providers to be aware of their unique needs. However, disclosure of a child’s autism spectrum disorder can be complex for parental caregivers and is not well understood. This qualit...

Background and objective: There is increasing recognition that children with autism spectrum disorder (ASD) experience challenges in busy clinical environments such as the emergency department (ED). ASD may heighten adverse responses to sensory input or transitions, which can impose greater difficulty for a child to cope with situational demands....

There is significant clinical heterogeneity in language and communication abilities of individuals with Autism Spectrum Disorders (ASD). However, no consistent pathology regarding the relationship of these abilities to brain structure has emerged. Recent developments in anatomical correlation-based approaches to map structural covariance networks (...

Objective: This study is the second of four to prepare International Classification of Functioning, Disability and Health (ICF; and Children and Youth version, ICF(-CY)) Core Sets for Autism Spectrum Disorder (ASD).The objective of this study was to survey the opinions and experiences of international experts on functioning and disability in ASD....

Objective: To describe services received by preschool children diagnosed with autism spectrum disorder (ASD) during the five-year period following their diagnosis. Method: An inception cohort of preschoolers diagnosed with ASD from Halifax (Nova Scotia), Montreal (Quebec), Hamilton (Ontario), Edmonton (Alberta) and Vancouver (British Columbia) w...

The Social ABCs is a parent-mediated intervention for toddlers with suspected or confirmed autism spectrum disorder (ASD). We undertook a multi-site pilot study to evaluate feasibility and acceptability, and to identify trends in child and parent behavior to inform future research using a larger sample and a rigorous research design. The program in...

Considerable evidence on autism spectrum disorder emergence comes from longitudinal high-risk samples (i.e. younger siblings of children with autism spectrum disorder). Diagnostic stability to age 3 is very good when diagnosed as early as 18–24 months, but sensitivity is weaker, and relatively little is known beyond toddlerhood. We examined stabili...

Children with autism spectrum disorder (ASD) are diagnosed, on average, around the age of 4 years. However, previous research has shown that the diagnosis can be made as early as 2 years, and that if the child is seen a year or more later, it is highly likely that the diagnosis will be confirmed. In this study, to examine whether diagnoses made as...

Mothers of children with an autism spectrum disorder (ASD) variably experience challenges in their caregiving role. This ethnographic study examined the caregiving experiences of mothers of a young person with ASD (aged ≤25 years). Semistructured interviews were conducted with 85 mothers across three Canadian regions. A follow-up subsample of 10 mo...

Siblings of children with autism spectrum disorder (ASD) who do not have ASD outcomes are more likely than their peers to experience delays in language acquisition as preschoolers. However, less is known about how these siblings are faring when they are school-aged. We examined language-related abilities of 18 siblings with non-ASD outcomes, aged 8...

This article reviews current evidence for autism spectrum disorder (ASD) screening based on peer-reviewed articles published to December 2013. Screening provides a standardized process to ensure that children are systematically monitored for early signs of ASD to promote earlier diagnosis. The current review indicates that screening in children age...

Early identification of autism spectrum disorder (ASD) is essential to ensure that children can access specialized evidence-based interventions that can help to optimize long-term outcomes. Early identification also helps shorten the stressful "diagnostic odyssey" that many families experience before diagnosis. There have been important advances in...

This article reviews current evidence for autism spectrum disorder (ASD) interventions for children aged < 3 years, based on peerreviewed articles published up to December 2013. Several groups have adapted treatments initially designed for older, preschool-aged children with ASD, integrating best practice in behavioral teaching methods into a devel...

Autism spectrum disorders (ASDs) are neurodevelopmental disorders characterized by impaired social communication skills and isolated areas of interest.1 The current prevalence of these disorders is estimated to be 1 in 68, 2 and recent estimates of the risk of recurrence in families with at least 1 child diagnosed with ASD are 10% to 19%.3-5 Advanc...

To explore commonly-held assumptions regarding the risk of couple breakdown in families of children with Autism Spectrum Disorder (ASD), a scoping review of quantitative (n=39), qualitative (n=14), and mixed (n=5) studies was conducted. Findings included themes related to marriage and divorce rates, quality of couple relationships, relationship con...

The use of genome-wide tests to provide molecular diagnosis for individuals with autism spectrum disorder (ASD) requires more study. To perform chromosomal microarray analysis (CMA) and whole-exome sequencing (WES) in a heterogeneous group of children with ASD to determine the molecular diagnostic yield of these tests in a sample typical of a devel...

The objective is to overview recent findings on early detection/diagnosis of autism spectrum disorders, as well as clinical trials of early interventions for toddlers at risk for/diagnosed with autism spectrum disorder. Prospective studies of infants at high risk of autism spectrum disorder have yielded significant advances in understanding early d...

Temperament was investigated in a group of high-risk infants (N = 383; 45 % girls) who had an older sibling with autism spectrum disorder (ASD), and in community control infants (N = 162; 46 % girls) with no family history of ASD (low-risk). The infants were assessed at age 12 months using the Infant Behavior Questionnaire, and at 24 months using t...

Prader-Willi syndrome (PWS) is a rare genetic disorder that results from lack of expression of paternally-derived genes on chromosome 15q11-13; caused by a deletion (DEL), uniparental disomy (UPD), or a rare imprinting center defect. PWS is associated with a distinct behavioral phenotype that in some respects overlaps with autism spectrum disorder...

To delineate the early progression of autism spectrum disorder (ASD) symptoms, this study investigated developmental characteristics of infants at high familial risk for ASD (HR), and infants at low risk (LR). Participants included 210 HR and 98 LR infants across 4 sites with comparable behavioral data at age 6, 12, and 24 months assessed in the do...

Community health care providers and other professionals involved in supporting optimal child development (eg, early childhood educators) play a critical role in working with parents to identify early signs of ASD. Screening and surveillance are complementary processes aimed at identifying children who require further assessment, with an overall goa...

BACKGROUND: In Canada, it is estimated that nearly one in three children are overweight or obese (Roberts et al., 2012). With a myriad of contributing factors and potential for serious long-term health consequences, overweight/obesity status constitutes an urgent and complex public health issue (Avis et al., 2014). Moreover, recent reports suggest...

Autism spectrum disorder is a complex neurodevelopmental disorder characterized by impaired social interaction and communication, repetitive behaviors, and restricted interests. Gray matter differences linked to autism spectrum disorder have been studied using a variety of structural imaging methods, but yielded little consensus; the extent to whic...

The increased male prevalence of autism spectrum disorder (ASD) may be mirrored by the early emergence of sex differences in ASD symptoms and cognitive functioning. The female protective effect hypothesis posits that ASD recurrence and symptoms will be higher among relatives of female probands. This study examined sex differences and sex of proband...

In most cases, autism spectrum disorders (ASD) can be reliably diagnosed at two to three years of age. However, Canadian data reveal a median age at diagnosis of approximately four years. To examine general paediatricians' practices regarding ASD screening and identify factors that influence decisions regarding the use of ASD screening tools. Using...

Numerous brain imaging studies indicate that the corpus callosum is smaller in older children and adults with autism spectrum disorder. However, there are no published studies examining the morphological development of this connective pathway in infants at-risk for the disorder. Magnetic resonance imaging data were collected from 270 infants at hig...

Background: Researchers often use the term ‘unaffected’ to describe siblings of children with ASD who do not have ASD outcomes; however, emerging evidence suggests that the developmental trajectories of many of these siblings are atypical. They are at greater risk of delayed language acquisition and communication impairments during the preschool ye...

Background: The diagnosis of autism spectrum disorder (ASD) made before age 3 has been found to be remarkably stable in clinic- and community-ascertained samples. The stability of an ASD diagnosis in prospectively ascertained samples of infants at risk for ASD due to familial factors has not yet been studied, however. The American Academy of Pedia...

We examined the stability of cognitive and adaptive behaviour standard scores in children with autism spectrum disorder (ASD) between diagnosis and school entry approximately age 6. IQ increased 18 points in 2-year-olds, 12 points in 3-year-olds, and 9 points in 4-year-olds (N = 281). Adaptive behaviour scores increased 4 points across age groups (...

This study is the first in a series of four empirical investigations to develop International Classification of Functioning, Disability and Health (ICF) Core Sets for Autism Spectrum Disorder (ASD). The objective was to use a systematic review approach to identify, number, and link functional ability and disability concepts used in the scientific A...

This prospective study characterized parents' concerns about infants at high risk for developing autism spectrum disorder (ASD; each with an older sibling with ASD) at multiple time points in the first 2 years, and assessed their relation to diagnostic outcome at 3 years. Parents of low-risk controls (LR) and high-risk infant siblings (HR) reported...

OBJECTIVE : The factor structure and validity of the Behavioral Pediatrics Feeding Assessment Scale (BPFAS; Crist & Napier-Phillips, 2001) were examined in preschoolers with autism spectrum disorder (ASD). METHODS : Confirmatory factor analysis was used to examine the original BPFAS five-factor model, the fit of each latent variable, and a rival on...

This review explores recent literature to prioritize aspects of development to be targeted by intervention for infants and toddlers with autism spectrum disorder (ASD). Recent investigation of early development in ASD, including prospective studies of infants at increased risk (i.e., those with an affected older sibling) identifies impairments in f...

Connectivity atypicalities in autism spectrum disorders (ASD) have been extensively proposed. The default mode network (DMN) is critical in this study given the insight it provides for long-distance connectivity, and the importance of regions in this network for introspection and social emotion processing, areas affected in ASD. Still, study of thi...

Autism spectrum disorder (ASD) is genetically heterogeneous, with evidence for hundreds of susceptibility loci. Previous microarray and exome-sequencing studies have examined portions of the genome in simplex families (parents and one ASD-affected child) having presumed sporadic forms of the disorder. We used whole-genome sequencing (WGS) of 85 qua...

Objective Younger siblings of children with autism spectrum disorder (ASD) are at high risk (HR) for developing ASD as well as features of the broader autism phenotype. While this complicates early diagnostic considerations in this cohort, it also provides an opportunity to examine patterns of behavior associated specifically with ASD compared to o...

Abstract Background: A key challenge in managing pediatric obesity is the high degree of program attrition, which can reduce therapeutic benefits and contribute to inefficient health services delivery. Our aim was to document and characterize predictors of, and reasons for, attrition in pediatric obesity management. We searched literature published...

Background: Differences in how developmental pathways interact dynamically in children with autism spectrum disorder (ASD) likely contribute in important ways to phenotypic heterogeneity. This study aimed to model longitudinal reciprocal associations between social competence (SOC) and language (LANG) pathways in young children with ASD. Methods:...

Introduction Participation in leisure activities is beneficial for children’s health and development, including those living with Autism Spectrum Disorder (ASD). Available syntheses of knowledge about participation have focused primarily on children with physical disabilities; however, little attention is directed to children with ASD. The purpose...

This paper examined early developmental trajectories in a large, longitudinal sample at high-risk for ASD (‘HR’) and low-risk (‘LR’) controls, and the association of trajectories with 3-year diagnosis. Developmental assessments were conducted at 6, 12, 24 months, and 3 years, with blinded “clinical best-estimate” expert diagnosis at age 3. HR infan...