Learning disabilities in a population-based group of children with hydrocephalus

To assess cognitive functions in a population-based group of children with hydrocephalus and to analyse differences between children with and without myelomeningocoele (MMC); with hydrocephalus already present at birth and those who developed it later; children born at full term and those born preterm.

Of 103 children with hydrocephalus born in the western-Swedish region in 1989-1993, 73 were assessed using the Wechsler Intelligence Scales or the Griffith Developmental Scales.

One-third of the children were normally gifted (IQ >85), another 30% had a low average IQ of 70-84 and 37% had learning disabilities with an IQ of <70. The median IQ was 75, verbal IQ 90 and performance IQ 76 (p<0.001). An IQ of <70 was found in 19 of 45 (42%) children without MMC and in 8 of 28 (29%) of those with MMC. Children born preterm had a lower IQ of 68 than those born at full term with an IQ of 76, while children with hydrocephalus present at birth but without MMC had a lower IQ of 60 than the others with an IQ of 77. Children with cerebral palsy and/or epilepsy (n=22) had a lower IQ of 66 than the IQ of 78 in those without these impairments (p<0.01).

Cognitive functions in children with hydrocephalus need to be carefully assessed before school age to ensure adequate support and education. Even the one-third near normally gifted children with an IQ of 70-85 require special attention, due to the profile of relatively well-preserved verbal functions but greatly impaired perceptual and non-verbal abilities.