[Characteristics of early cognitive development in children with Williams syndrome: a prospective cohort study]

Objectives: To investigate the early cognitive development characteristics of children with Williams syndrome (WS) at different age stages.

Methods: From September 2018 to June 2023, 106 children diagnosed with WS at the Department of Pediatric Health Care, Children's Hospital, Zhejiang University School of Medicine, aged 1 to <5 years, were prospectively enrolled. All children underwent Gesell developmental diagnostic assessments to analyze the cognitive development characteristics of WS children across different age groups.

Results: The average age of the 106 WS children was (3.1±1.2) years; 58 were male, and 48 were female. There were no significant differences in developmental levels between males and females in the five domains of gross motor skills, fine motor skills, language, personal-social skills, and adaptive behavior (P>0.05). The incidence rates of mild, moderate, severe, and profound developmental disabilities among children of different age groups showed no significant differences (P>0.05). Comparisons of developmental levels in gross motor skills, language, personal-social skills, and adaptive behavior among different age groups were also not statistically significant (P>0.05). With the increase of age, the developmental level of fine motor skills showed a decreasing trend (P<0.05). There were no significant differences in verbal IQ and non-verbal IQ within each age group of WS children (P>0.05).

Conclusions: The overall developmental level of WS children stabilizes with age, and their early language abilities do not significantly exceed their non-verbal abilities.