Sex Differences in Autistic Youth Born Extremely Preterm

Area of Science:

• Neurodevelopmental Disorders
• Pediatric Psychology
• Genetics and Genomics

Background:

• Autism Spectrum Disorder (ASD) is a neurodevelopmental condition affecting social interaction and communication.
• Sex differences in ASD prevalence and symptom presentation are well-documented in full-term populations.
• Extremely preterm (EP) birth is a risk factor for ASD, but sex-specific autistic traits in this population are less understood.

Purpose of the Study:

• To investigate sex differences in autistic traits among children diagnosed with ASD who were born extremely preterm (EP).
• To compare autistic traits using gold-standard diagnostic measures and screening tools at 10 years of age.

Main Methods:

• A longitudinal cohort of 857 EP infants (23-27 weeks gestation) from the Extremely Low Gestational Age Newborn Study (ELGAN) was followed to 10 years.
• Sixty-one EP infants diagnosed with ASD (20 females) were analyzed for sex differences in autistic traits.
• Data were collected using ASD screeners (M-CHAT, SCQ, SRS-2) and diagnostic measures (ADOS-2, ADI-R), with analyses including inferential and Bayesian statistics.

Main Results:

• Males scored significantly higher than females on Social Affect (ADOS-2) and Repetitive and Restricted Behaviors (ADI-R).
• Marginal evidence suggested males scored higher on Nonverbal and Verbal Communication (ADI-R).
• No significant sex differences were found on ASD screeners (M-CHAT, SCQ, SRS-2) at 2 or 10 years.

Conclusions:

• Extremely preterm autistic males exhibit more autistic traits than females on diagnostic assessments at 10 years.
• These findings parallel sex differences observed in full-term autistic youth.
• Current ASD screeners may under-identify autism in EP youth, particularly females, highlighting a need for improved diagnostic approaches.