[Long-term cognitive dysfunctions related to prematurity]

Little is understood about the effects of prematurity on long-term cognitive functioning. No detailed studies have been carried out in a Spanish population to investigate the cognitive performance of adolescents who were born preterm.

To utilise the Wechsler intelligence scales to examine the performance of a broad sample of adolescents who were born preterm, to describe the clinical significance of this performance and to analyse the discriminatory powers of the different subtests.

The intelligence quotients of 62 preterm subjects and 62 controls were evaluated by administering the full Wechsler intelligence scales. A number of specific neuropsychological functions were also assessed.

Significant differences were observed in the overall, verbal and manipulative intelligence quotients, as well as in most of the subtests, although less than 30% of the preterm subjects displayed any alterations in their performance. The subtests that were most sensitive to the poor performance of the preterm subjects were vocabulary, coding and picture arrangement. The significant differences in learning, memory, cognitive flexibility and verbal fluency were not upheld on controlling for general cognitive performance.

Adolescents with a history of prematurity as a group offer low performance on the Wechsler intelligence scale, although most of them achieve scores within the range of what can be considered to be normal. The different subtests that make up this scale do not exhibit the same degree of sensitivity when evaluating the possible difficulties preterm adolescents have in cognitive performance.