Declining incidence of cerebral palsy in South Korea: Linked analysis of the National Health Insurance database and the health screening data

Abstract

Background Presuming that the prevalence of cerebral palsy (CP) in Korea is decreasing due to medical advances, we analyzed the trends and risk factors of CP in changing circumstances. Methods We identified all women who delivered a singleton between 2007 and 2015 using the Korea National Health Insurance (KNHI). Information on pregnancy and birth was obtained by linking the KNHI claims database and data from the national health-screening program for infants and children. Results Over 90% of children with CP were diagnosed within four years of birth. Moreover, the 4-year incidence of CP decreased significantly from 4.77 to 2.52 per 1000 babies during the study period. Multivariate analysis showed that the risk of developing CP was 3.9 times higher in babies with preterm birth, 5.6 times higher in those with birth weight <2500 g, and 4.1 times higher in pregnancies with polyhydramnios. Over time, the number of preterm births and babies with low birth weight decreased, while polyhydramnios became slightly more prevalent. Conclusion In Korea, the incidence of CP in singleton decreased from 2007 to 2015. In addition, the number of preterm births and babies with a low birth weight, which are major risk factors for CP, also declined.