Medical Conditions and Early Development in Toddlers With Down Syndrome

OBJECTIVE: To examine the associations between medical conditions and early developmental skills in young children with Down syndrome (DS). METHOD: Data were drawn from the first timepoint of a longitudinal study of children with DS (n = 114; mean age = 20.6 months). Caregivers completed a comprehensive medical history questionnaire, followed by a structured interview and review by a medical doctor to clarify endorsed conditions. Cognitive, expressive, and receptive communication, and fine and gross motor developments were assessed using the Bayley Scales of Infant and Toddler Development, Fourth edition. Associations between medical condition categories and developmental skills across domains were examined using partial correlations adjusting for age. Dominance analyses assessed the unique contributions of significant medical categories. RESULTS: Vision conditions were associated with lower developmental scores across cognitive, communication, and gross motor domains. Seizure/epilepsy was associated with lower cognitive, expressive communication, and motor domain scores. Length of neonatal intensive care unit stay was associated with lower cognitive and communication scores. Additional factors, including premature birth, structural gastrointestinal conditions, dysphagia, eczema, and thyroid disease, were associated with lower scores in specific developmental domains. Dominance analyses revealed overlapping contributions across significant predictors with each developmental domain. CONCLUSION: Findings highlight the associations between co-occurring medical conditions and developmental heterogeneity among young children with DS. Results underscore the need for further work, including longitudinal research studies, to clarify the role of medical conditions in shaping neurodevelopment in DS.