Developmental Trajectories of Autistic Traits in Infants With Autism and/or ADHD Family History: Predictors and Mid-Childhood Outcomes
Year: 2026
Type: article
Study design: Observational Study
Abstract: PURPOSE: Autism is both a developmental and heterogeneous condition, with individual variation in the timing and shape of autistic symptom trajectories over time, as recognised by the concept of 'chronogeneity'. Prospective infant autism family history studies are well-suited to examining developmental trajectory variability, a key aspect of autism trait heterogeneity. METHODS: We examined autistic trait trajectories in a large sample of infants with autism and/or ADHD family history (N = 384) followed from infancy to mid-childhood. Using group-based multi-trajectory modelling, we identified classes with distinct trajectories across three autism trait measures taken at six, five, and four timepoints, respectively, between 5 months and 9 years. RESULTS: A 5-class solution provided the best fit. Three classes included 50-75% children meeting autism diagnostic criteria at 3 years or mid-childhood, with distinct differences in timing, onset, and developmental patterns of autistic traits. Two classes were predominantly typically developing, with one characterised as 'slow starters'. Background characteristics including autism/ADHD family history, sex, maternal education, and household income (but not ethnicity) predicted class membership. Mid-childhood outcomes-IQ, adaptive function, autism and ADHD traits, anxiety and behavioural difficulties-differed across trajectory classes. CONCLUSION: The timing and developmental course of autistic traits-independent of trait level-relate meaningfully to infant and family characteristics, diagnostic timing, and mid-childhood outcomes. These findings support chronogeneity as a valuable framework for understanding autism heterogeneity in family history studies. The trajectory classes identified here are descriptive; future studies should examine their replicability, and explanatory and mechanistic value.
Authors: Tony Charman, Tessel Bazelmans, Greg Pasco, Jannath Begum Ali, Emily J. H. Jones, Mark H. Johnson, The BASIS/STAARS Team, Rowan Arthur, Jeni Baykoca, Anna Blasi, Patrick Bolton, Celeste Cheung, Kenny Chiu, Leila Dafner, Kim Davies, Mayada Elsabbagh, Janice Fernandes, Laurel Fish, Isobel Gammer, Teodora Gliga, Jeanne Guiraud, Rianne Haartsen, Sarah Kalwarowsky, Anna Kolesnik, Michelle Liew, Sarah Lloyd-Fox, Helen Maris, Luke Mason, Mia Medas, Bosiljka Milosavljevic, Louise O’Hara, Andrew Pickles, Laura Pirazzoli, Helena Ribeiro, Erica Salomone, Elizabeth Shephard, Chloë Taylor, Leslie Tucker
Language: English
Subfield: Cognitive Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,190
Funders: Autism Speaks, Autistica, Maudsley Charity, European Federation of Pharmaceutical Industries and Associations, Government of the United Kingdom, UK Research and Innovation, Simons Foundation Autism Research Initiative, Guy's and St Thomas' Charity, European Commission, HORIZON EUROPE Framework Programme, Medical Research Council, Staatssekretariat für Bildung, Forschung und Innovation, HORIZON EUROPE European Innovation Council
Awards: Developmental Trajectories in Autism Spectrum Disorder from 6 months to 7 years, G2633270591, Risk and Resilience in Developmental Diversity and Mental Health, Risk and Resilience in Developmental Diversity and Mental Health, G4345436876, Development of somatosensation in preterm infants: a neonatal precursor of sensory processing disorders in childhood, G452649895, G4612562667, G4668817743, G5543596241, G5706255847, G60524263, The Development of Social, Attention, and Perception Abilities in Typical and At-risk Infants, Autism Innovative Medicine Studies – 2 – Trials, G6972650492, G7051064115, G7070717597, Human neurocognitive development: Early-stage processing, modifiers, and outcomes, G8180280471, G8563726104, G8614269777
OpenAlex ID: W7204166692