Developmental profiles and mentality in preschool children with Prader-Willi syndrome: a preliminary study.

Background: A majority of the children with Prader-Willi syndrome (PWS) have global developmental delay and mental delay. The aim of this study was to investigate the developmental profiles and mental assessments among preschool children with PWS.

Methods: Ten children with PWS between the ages of 15 months to 6 years, and 11 children with typical development were enrolled. Developmental profiles in terms of their developmental quotient (DQ) for the eight domains of the Chinese Children Developmental Inventory (CCDI) and mental assessments in terms of intelligence quotient (IQ) and developmental index (DI) were carried out for all children.

Results: The DQs of all eight domains, including gross motor, fine motor, expressive language, concept comprehension, situation comprehension, self help, personal- social and general development, in the PWS group were lower than the DQs of the children from the typical development group (p < 0.01). Children with PWS had better DQs in the fine motor domain than in the gross motor domain and in the receptive language domain than in the expressive language domain. Furthermore, their verbal IQ were better than their performance IQ and their mental DI was better than their psychomotor DI.

Conclusions: These findings suggest that the children with PWS show an uneven global developmental delay together with an uneven mental delay. The results of this study should allow clinicians to better understand the developmental functioning of children with PWS and this will help with the planning of treatment strategies.