Effects of cognitive, motor, and sensory disabilities on survival in cerebral palsy
- 1Department of Statistics, University of Warwick, Coventry CV4 7AL, UK
- 2Emeritus Professor, FSID Unit of Perinatal and Paediatric Epidemiology, University of Liverpool, Liverpool L69 3BX, UK
- Correspondence to:
Dr J L Hutton, Department of Statistics, University of Warwick, Coventry CV4 7AL, UK;
- Accepted 25 June 2001
Background: Cerebral palsy presents with a range of severity of cognitive, motor, and sensory disabilities, which might affect survival.
Aims: To quantify the effects of motor, cognitive, and sensory disabilities, year of birth, birth weight, and gestational age on survival in cerebral palsy.
Methods: A cohort of children with cerebral palsy born between 1966 and 1989 to mothers resident in a defined geographical region was subdivided into early impairment (EICP: cerebral insult prenatally or within 28 days of birth) or late impairment (LICP: insult at least 28 days after birth). Deaths are notified by the National Health Service Central Register. Birth and disability details were obtained from clinical records. Survival analyses were carried out.
Results: Severe motor disability was associated with a 30 year survival of 42% and severe cognitive disability with a 30 year survival of 62%. Severe visual disability was associated with a 30 year survival of 38%, but the association of survival with hearing disability was weak. EICP had better survival than LICP but the difference was not significant after allowing for severity of functional disabilities. Normal birth weight infants (≥2500 g) showed no birth cohort effect, but the 10 year survival of low birth weight (<2500 g) infants declined from 97% for 1966 to 89% for 1989 births.
Conclusions: Survival in cerebral palsy varies according to the severity and number of functional disabilities and by birth weight. Among low birth weight children, survival declined steadily from 1966 to 1989 after allowing for disability. The disabilities reported do not capture all the factors affecting survival of preterm infants.
- EICP, early impairment cerebral palsy
- IQ, intelligence quotient
- LICP, late impairment cerebral palsy
We thank Theresa Cooke for her meticulous compilation of the Mersey Cerebral Palsy Register and Beverley Botting and her staff at the Office for National Statistics for providing the death registration data.
Funding for maintaining the Mersey Cerebral Palsy Register has been provided by the National Health Service, the North West Region Research and Development executive, and by Children Nationwide.