A scoping review of observation studies of overweight/obese children with intellectual disabilities in East Asian countries: China, Korea, Taiwan, Hong Kong and Japan

There have been several current review studies on factors influencing obesity in children worldwide (1) , however, these have not investigated children with intellectual disabilities in whom a higher prevalence of obesity rate has been reported. The aim of the study is to compare the prevalence of obesity and to discuss the potential factors influencing obesity in children with intellectual disabilities. This scoping review was based on the JBI scoping review (1) with reference to the PubMed, CINAHL, Medline and Ichushi-Web (in Japanese). Search terms included “obesity” and “children with intellectual disabilities,” “China”, “South Korea”. “Hong Kong”, “Taiwan”, “Mongolia” or “Japan”. The inclusion criteria were: papers should be published in English or Japanese; the full-text articles appear in peer-reviewed journals; the research targeted children with intellectual disabilities (aged 3-18 years). The exclusion criteria were reviews, case reports, intervention studies, proceedings and studies targeting specific patients, such as those presenting with Prader-Willi syndrome, Bardet-Biedl syndrome, Baraitser-Winter syndrome, Cohen syndrome and mental health disorders. Autism and Down’s Syndrome were included. The results were screened by two people. In total, 13 studies were identified: 46% (6 studies) from China, Japan (3 studies) and South Korea and Taiwan (2 studies, respectively), Hong Kong (1 study), however no research was found on Mongolia. Children with intellectual disabilities and those with autism were targeted by 5 studies, whereas 3 studies were conducted on obesity in children with Down’s Syndrome. The obesity rate varied between studies. A Taiwanese study targeting children with Down’s Syndrome reported the prevalence of overweight or obese children to be 83%. Whereas other studies reported the prevalence to be around 30% in Taiwanese children with intellectual disabilities, around 30% in Chinese children with intellectual disabilities, and around 20% in Japanese children. These findings determined that children with intellectual disabilities are more at risk of becoming overweight or obese than typically developing children. The obesity related factors reported included Down’s Syndrome or autism, older age group, reduced physical activity, longer sedentary behaviour, poor sleep quality, intake of sweets and juice, and less healthy parents (2,3,4) . It is unclear whether gender was a contributory factor as although the Chinese study indicated that boys were more likely to be obese (5) , the Korean study suggested that girls were more likely to be obese (6) . Obesity rates of children with intellectual disabilities was varied from 20%-30% or over. The main factors related to obesity in this population include the amount of time the children engaged in physical activity and the intake of sweets or juice, as well as parental factors which also affected the children’s physical status. It is recommended that more research be conducted on the factors contributing to obesity in children with intellectual disabilities including parental factors.