Mortality in childhood progressive encephalopathy from 1985 to 2004 in Oslo, Norway: a population-based study

AIMS: The aims were to estimate case fatality and survival rates, standardized mortality ratio (SMR), and independent prognostic factors for survival, in a population-based cohort of progressive encephalopathy (PE) patients. METHODS: We divided onset of disease into neonatal and postneonatal groups and aetiology into metabolic (n=55), neurodegenerative (n=27) and HIV encephalopathy (n=2) groups. Case fatality was the number of deaths divided by the number of patients. Cumulative survival probability at 10 years of follow-up and independent risk factors for mortality were analyzed using the Kaplan-Meier survival curve and the Cox model. RESULTS: Case fatality was 36.9% and the mean and median follow-up times were 3109 and 2887 days. At 1 and 10 years, the cumulative probability of survival was 81% and 66%. Neonatal onset showed increased risk of death compared to postneonatal onset (RR 3.0; 95% CI 1.4-6.2). Metabolic aetiology showed increased risk of death compared to other aetiology (RR 1.25; 95% CI 1.10-1.46). The SMR of 37.7 for boys and 23.8 for girls was significantly increased (p<0.001) compared to the total Norwegian population stratified by gender and age. CONCLUSIONS: Children with PE showed a vast excess in mortality compared to the general population stratified by gender and age. Neonatal presentation and metabolic aetiology were the most significant factors for increased risk of death.