An epidemiological survey of severely mentally and physically disabled children in Okinawa

A survey of severely mentally and physically disabled children (SDC) aged 6-15 years was conducted in Okinawa. There were a total of 170 SDC on 1 May 1989, the prevalence rate being 0.89/1,000. The prevalence rate of SDC over the last 20 years has shown a decreasing trend, which seems to be associated with the decreased incidence of cerebral palsy (CP) in the latter half of the 1970s and the first half of the 1980s. Furthermore, CP accounted for the largest percentage (51.8%) of underlying disorders or conditions of SDC, similar to 20 years ago. This suggests that the incidence of CP could be an important factor in the prevalence of SDC. In addition, the percentages of SDC with CP with profound mental impairment and epilepsy, 97.7% and 79.5%, respectively, were larger than 20 years ago. This suggests that SDC with CP who have severe associated impairments have increased.