A Clinical Study on Mental Retardation of Preschool Children Diagnosed in Pediatric Developmental Clinic

Kim, Young Yeui; Sung, In Kyung

Abstract

PURPOSE
Mental retardation, which can be defined as subnormal cognitive ability with markedly decreased ability to adapt to one's environment, is a common developmental disorder. But the diagnosis of mental retardation in young children is frequently missed in pediatric clinics. The purpose of this study is to increase the rate of early diagnosis and intervention by providing clinical information about mental retardation in early childhood.
METHODS
Clinical observations of 72 mental retarded children diagnosed in the Pediatric Developmental Clinic of St. Mary's Hospital of Catholic University Medical College were made. Mental retardation was defined as Mental Developmental Index of Bayley Scales of Infant Development-II or IQ of Wechsler Intelligence Preschool Primary Scale of Intelligence-Revised below 70. Children of IQs below 50 were classified as serious mental retardation and IQs between 50-70 as mild mental retardation.
RESULTS
The mean age of diagnosis of mental retardation was 23+/-11 months; median was 19 months old. Children with serious mental retardation consisted of 47.2% of the total. 50.0% of patients visited the developmental clinic via private pediatric clinics. The etiology of mental retardation was not identified in 45.8% of cases; postnatal, perinatal and prenatal causes were found in 27.8%, 20.8% and 5.6%, respectively. The most frequent chief complaints were motor developmental disorder and speech and language disorders. Delay in gross motor milestone was observed in 63.9% of patients. 55.0% of patients received brain CTs or MRI revealed abnormal findings. The most common associated impairment was speech and language disorder with a prevalence rate of 62.5%. A variety of therapeutic procedures were provided for the mental retarded children, including early intervention, physical therapy, special education, nutritional support, speech therapy and behavioral management.
CONCLUSION
As a primary heath provider, pediatricians could make earlier diagnosis of mental retardation in young children by understanding the variety of clinical findings of this common pediatric disorder.