Profile of Autism Spectrum Disorder in Tuberous Sclerosis Complex: Results from a Longitudinal, Prospective, Multisite Study.

OBJECTIVE: Tuberous sclerosis complex (TSC) is highly associated with autism spectrum disorder (ASD). Objectives of the study were to characterize autistic features in young children with TSC. METHODS: Participants included 138 children followed from ages 3 to 36 months with TSC from the Tuberous Sclerosis Complex Autism Center of Excellence Research Network (TACERN), a multicenter, prospective observational study aimed at understanding the underlying mechanisms of ASD in TSC. Developmental and autism-specific assessments were administered, and a clinical diagnosis of ASD was determined for all participants at 36 months. Further analyses were performed on 117 participants with valid autism assessments based on nonverbal mental age greater than 15 months. RESULTS: Prevalence of clinical diagnosis of ASD at 36 months was 25%. Nearly all autistic behaviors on the Autism Diagnostic Observation Schedule-2 (ADOS-2) and Autism Diagnostic Interview-Revised (ADI-R) were more prevalent in children diagnosed with ASD; however, autism-specific behaviors were also observed in children without ASD. Overall quality of social overtures, facial expressions, and abnormal repetitive interests and behaviors were characteristics most likely to distinguish children with ASD from those without an ASD diagnosis. Participants meeting ADOS-2 criteria but not a clinical ASD diagnosis exhibited intermediate developmental and ADOS-2 scores compared to individuals with and without ASD. INTERPRETATION: ASD is highly prevalent in TSC, and many additional individuals with TSC exhibit a broad range of subthreshold autistic behaviors. Our findings reveal a broader autism phenotype that can be identified in young children with TSC, which provides opportunity for early targeted treatments. ANN NEUROL 2021;90:874-886.

Influence of seizures on early development in tuberous sclerosis complex.

OBJECTIVE: Epilepsy is commonly seen in Tuberous Sclerosis Complex (TSC). The relationship between seizures and developmental outcomes has been reported, but few studies have examined this relationship in a prospective, longitudinal manner. The objective of the study was to evaluate the relationship between seizures and early development in TSC. METHODS: Analysis of 130 patients ages 0-36months with TSC participating in the TSC Autism Center of Excellence Network, a large multicenter, prospective observational study evaluating biomarkers predictive of autism spectrum disorder (ASD), was performed. Infants were evaluated longitudinally with standardized evaluations, including cognitive, adaptive, and autism-specific measures. Seizure history was collected continuously throughout, including seizure type and frequency. RESULTS: Data were analyzed at 6, 12, 18, and 24months of age. Patients without a history of seizures performed better on all developmental assessments at all time points compared to patients with a history of seizures and exhibited normal development at 24months. Patients with a history of seizures not only performed worse, but developmental progress lagged behind the group without seizures. All patients with a history of infantile spasms performed worse on all developmental assessments at 12, 18, and 24months. Higher seizure frequency correlated with poorer outcomes on developmental testing at all time points, but particularly at 12months and beyond. Patients with higher seizure frequency during infancy continued to perform worse developmentally through 24months. A logistic model looking at the individual impact of infantile spasms, seizure frequency, and age of seizure onset as predictors of developmental delay revealed that age of seizure onset was the most important factor in determining developmental outcome. CONCLUSIONS: Results of this study further define the relationship between seizures and developmental outcomes in young children with TSC. Early seizure onset in infants with TSC negatively impacts very early neurodevelopment, which persists through 24months of age.

Improving Access to Diagnostic Assessments for Autism Spectrum Disorder Using an Arena Model.

OBJECTIVE: To improve access to diagnostic evaluations for children younger than 3 years with concerns for possible autism spectrum disorder. METHODS: A multidisciplinary "arena model" for children younger than 3 years was developed, tested, and implemented over an approximately 2-year period. Arena assessment teams comprised a developmental behavioral pediatrician (DBP), psychologist, and speech language pathologist (SLP). Quality improvement methods were used during the design phase, conducting Plan-Do-Study-Act (PDSA) cycles and collecting feedback from key stakeholders, and during implementation, plotting data on run charts to measure outcomes of the time to initial visit and time to diagnosis. RESULTS: Over the 9-month implementation period, 6 arena assessment teams were formed to provide 60 evaluation slots per month for children younger than 3 years. The time to first visit was reduced from a median of 122 days to 19 days, and the time to final diagnosis was reduced from 139 days to 14 days, maintaining these outcomes at <35 and <18 days, respectively, over a 2-year period. Total visits required decreased from 4 to 5 visits to just 2 visits, and the average assessment cost was reduced by $992 per patient. Feedback from both providers and families participating in this model was overwhelmingly positive. CONCLUSION: Access for young children referred for developmental assessments can be improved through an understanding of supply and demand and the development of creative and flexible care delivery models.

Impacting development in infants with tuberous sclerosis complex: Multidisciplinary research collaboration.

The Tuberous Sclerosis Complex Autism Center of Excellence Network (TACERN) is a 6-site collaborative conducting longitudinal research on infants with tuberous sclerosis complex (TSC), focused on identifying early biomarkers for autism spectrum disorder (ASD). A multidisciplinary research team that includes the specialties of psychology, neurology, pediatrics, medical genetics, and speech-language pathology, its members work together to conduct studies on neurological status, brain structure and function, neurodevelopmental phenotype, and behavioral challenges in this population. This article provides insights into the roles of the multidisciplinary multisite team and lessons learned from the collaboration, in terms of research as well as training of future researchers and clinicians. In addition, the authors detail the major findings to date, including those related to the identification and measurement of early symptoms of ASD, relationship between seizures and early development, and early biomarkers for epilepsy and developmental delay in infants and young children with TSC. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Utility of the Autism Observation Scale for Infants in Early Identification of Autism in Tuberous Sclerosis Complex.

BACKGROUND: Tuberous sclerosis complex (TSC) is a genetic disorder with high prevalence of associated autism spectrum disorder (ASD). Our primary objectives were to determine early predictors of autism risk to identify children with TSC in most need of early interventions. The Autism Observation Scale for Infants (AOSI) was evaluated as a measure of ASD-associated behaviors in infants with TSC at age 12 months and its ability to predict ASD at 24 months. METHODS: Children ages 0 to 36 months with TSC were enrolled in the TSC Autism Center of Excellence Research Network (TACERN), a multicenter, prospective observational study to identify biomarkers of ASD. The AOSI was administered at age 12 months and the Autism Diagnostic Observation Schedule-2 (ADOS-2) and Autism Diagnostic Interview-Revised (ADI-R) at 24 months. Developmental functioning was assessed using the Mullen Scales of Early Learning. Children were classified as ASD or non-ASD according to the ADOS-2. RESULTS: Analysis included 79 children who had been administered the AOSI at 12 months and ADOS-2 and ADI-R at 24 months. The ASD group had a mean AOSI total score at 12 months significantly higher than the non-ASD group (11.8 ± 7.4 vs 6.3 ± 4.7; P < 0.001). An AOSI total score cutoff of 13 provided a specificity of 0.89 to detect ASD with the ADOS-2. AOSI total score at 12 months was similarly associated with exceeding cutoff scores on the ADI-R. CONCLUSIONS: The AOSI is a useful clinical tool in determining which infants with TSC are at increased risk for developing ASD.