Low birth score linked to cerebral palsy

Having a low score on a simple vitality test at birth is strongly linked with later diagnosis of cerebral palsy, Norwegian researchers have found.

The Apgar score is a quick and simple assessment of a baby's condition at birth. Doctors and nurses assess the baby on five criteria — complexion, pulse rate, reaction when stimulated, muscle tone, and breathing. 

'Most infants with such [low] scores recover quickly and do well.' — Nigel Paneth

Cerebral palsy is a rare disease, affecting two to three infants in every 1,000 live born children in developed countries.

Studies have suggested a strong link between low Apgar scores and cerebral palsy in children born to term or with a normal body weight, but the findings in preterm infants or low birth weight are less clear.

Using data from the Medical Birth Registry of Norway and the Norwegian Registry of Cerebral Palsy in Children, researchers looked at the link between Apgar score five minutes after birth and cerebral palsy and 543,000 children born between 1986 and 1995.

A total of 988 children included in the study (1.8 in 1,000) were diagnosed with cerebral palsy before the age of five years.

The prevalence of cerebral palsy in children with Apgar score of less than three out of 10 was more than 100-fold higher than in children with a score of 10, Kari Kveim Lie of the Norwegian Institute of Public Health in Oslo and co-authors found.

"Despite the strong association of low Apgar score with cerebral palsy, it is encouraging that almost 90 per cent of children with an Apgar score of less than four at birth did not develop cerebral palsy," the study's authors wrote in Friday's issue of BMJ.

'Important clue'

Low Apgar score was also associated with all types of spastic cerebral palsy, but the link was strongest for quadriplegia.

The association was high in children with normal birth weight and modest in children with low birth weight, the researchers said.

A low Apgar score, especially when it persists beyond the first minute of life, is an indicator of central nervous system depression, so it is not surprising it can predict later neurological problems, Prof. Nigel Paneth of the College of Human Medicine from Michigan State University said in journal editorial accompanying the study.

A low Apgar score in a baby of normal weight "is an important clue that the baby has an increased risk of death and disability, even though most infants with such scores recover quickly and do well," Paneth said.

Such babies should be watched closely for the development of signs of brain damage, Paneth advised.