[A study on incidence of developmental disabilities in Higashi-Osaka City, Japan, 1988-1992]

A population based statistical analysis was performed of the incidence of developmental disabilities in Higashi-Osaka, a city in Osaka Prefecture with a population of about 500,000. The number of live births during 1988-1992 was 24,980, of whom those with cerebral palsy (CP), severe motor and intellectual disability syndrome (SMIDS), infantile autism, mental retardation (MR) and Down syndrome numbered 30, 21, 26, 268 and 25, respectively. And the respective incidence rates per 1,000 were 1.20, 0.84, 1.04, 10.7 and 1.0. For CP, the percentage of premature children was 63%, higher than in previous reports. Extremely low-birth-weight premature children (< 999 g birth weight) were especially notable at 20% of the CP total. For SMIDS, it is more important to understand the significance of medical care to support sufferers' social lives. High functional autistic children could not be evaluated at our center, though autism accounted for 8.6% of mental retardation. The medical functions of community institutions enable them to perform continuous, population based study of the incidence and situation of developmental disabilities.