Cerebral palsy in Norway: prevalence, subtypes and severity

To describe prevalence, subtypes and severity of cerebral palsy (CP) in Norway using criteria proposed by the Surveillance of Cerebral Palsy in Europe (SCPE) network.

All children in Norway with CP born in January 1996-December 1998 were registered in the Cerebral Palsy Registry of Norway. The Medical Birth Registry of Norway provided the perinatal data.

A total of 374 children with CP were identified with a prevalence of 2.1 per 1000 live births. Detailed information was obtained from 294 (79%) children. Median age at clinical assessment was 6.9 years (range: 1.9-10.2 years). Thirty-three percent of the children had spastic unilateral CP, 49% spastic bilateral, 6% dyskinetic, 5% ataxic CP and 7% were not classified. Severely impaired vision and hearing were present in 5% and 4% of the children, respectively. Active epilepsy was present in 28%, mental retardation in 31% and severely impaired or no speech in 28% children. The most severe impairments in gross motor function were observed in children with low Apgar scores, and the most severe impairments in fine motor function in children born at term, with normal birth weight and low Apgar scores.

Compared with other populations, the prevalence of CP as well as the proportions of subtypes and gross motor impairments were similar, whereas fine motor impairments and associated impairments were more common. The classification of children with mixed forms of CP is still a challenge. Children were more severely affected if Apgar scores were low, and if they were born at term.