Long-term survival of children with cerebral palsy in Okinawa, Japan

Abstract

Aim: The aim of this study was to describe the survival prognosis of children with cerebral palsy (CP) in Okinawa, Japan.

Method: A cohort study was conducted on all children with CP born between 1988 and 2005 in Okinawa, Japan. Survival proportions were determined with a life table and Kaplan-Meier survival curves were plotted. The effect of each predictor variable was estimated using Cox regression analysis.

Results: This study included 580 children with CP (332 males, 248 females). In the cohort, 119 (20.5%) children were classified in Gross Motor Function Classification System (GMFCS) level I, 65 (11.2%) were classified in level II, 40 (6.9%) in level III, 189 (32.6%) in level IV, 166 (28.6%) in level V and GMFCS level was unknown for one. Of the 34 children who died, 29 were classified in GMFCS level V and GMFCS level was unknown for one. Mean age at start of follow-up was 24.5 months (SD 2.6 mo); mean length of follow-up was 8 years 8 months (standard error of the mean 0.214 y). The 5 year- and 18-year survival percentages of the entire cohort were 98% and 89% respectively. In children with CP, significantly lower survival rates were associated with multiple factors, including a birthweight of at least 2500 g (p=0.009), a gestational age of at least 37 weeks (p=0.004), and the most severe gross motor limitation, GMFCS level V (p<0.001). However, multivariate analysis showed GMFCS level V was the only significant predictor variable (p<0.001) for survival of CP.

Interpretation: This study is the first to describe survival of children with CP in Japan. Our results are similar to those previously reported in other countries. These results are important in planning adequate provision of social and medical services for individuals with CP.