Life expectancy among people with cerebral palsy in Western Australia

This report describes trends, predictors, and causes of mortality in persons with cerebral palsy (CP) using individuals identified by the Western Australian Cerebral Palsy Register and born between 1958 and 1994. Two thousand and fourteen people were identified (1154 males, 860 females), of whom 225 had died by 1 June 1997. Using date-of-death data, crude and standardized mortality rates were estimated and predictors of mortality sought using survival analysis stratified by decade of birth, description of impairments, and demographic and perinatal variables. For those born after 1967, the cause of death profile was examined over time. Mortality exceeded 1% per annum in the first 5 years and declined to age 15 years after which it remained steady at about 0.35% for the next 20 years. The strongest single predictor was intellectual disability, but all forms of disability contributed to decreased life expectancy. Half of those with IQ/DQ score <20 survived to adulthood, increasing to 76% with IQ/DQ score 20-34, and exceeding 92% for higher scores. Severe motor impairment primarily increased the risk of early mortality. Despite there being 72 persons aged from 25 to 41 years with severe motor impairment in our data set, none had died after the age of 25 years. Infants born after more than 32 weeks' gestation were at significantly higher risk of mortality than very preterm infants, accounted for by their higher rates of intellectual disability. No improvements in survival of persons with CP were seen over the study period despite advances in medical care, improved community awareness, and the increasing proportion of very preterm births among people with CP. This may be the result of improved neonatal care enabling the survival of infants with increasingly severe disabilities.