Judy M. Briët

Development and evaluation of a follow up assessment of preterm infants at 5 years of age

Background: Long term follow up shows a high frequency of developmental disturbances in preterm survivors of neonatal intensive care formerly considered non-disabled. Aims: To develop and validate an assessment tool that can help paediatricians to identify before 6 years of age which survivors have developmental disturbances that may interfere with normal education and normal life. Methods: A total of 431 very premature infants, mean gestational age 30.2 weeks, mean birth weight 1276 g, were studied at age 5 years. Children with severe handicaps were excluded. The percentage of children with a correctly identified developmental disturbance in the domains cognition, speech and language development, neuromotor development, and behaviour were determined. Results: The follow up instrument classified 67% as optimal and 33% as at risk or abnormal. Of the children classified as at risk or abnormal, 60% had not been identified at earlier follow up assessments. The combined set of standardised tests identified a further 30% with mild motor, cognitive, or behavioural disturbances. The paediatrician’s assessment had a specificity of 88% (95% CI 83–93%), a sensitivity of 48% (95% CI 42–58%), a positive predictive value of 85% (95% CI 78–91%), and a negative predictive value of 55% (95% CI 49–61%). Conclusions: Even after standardised and thorough assessment, paediatricians may overlook impairments for cognitive, motor, and behavioural development. Long term follow up studies that do not include detailed standardised tests for multiple domains, especially fine motor domain, may underestimate developmental problems.

THYROXINE SUPPLEMENTATION IN INFANTS |[bull]| 1679

Background: Transient hypothyroxinemia is a common phenomenon in preterm infants. An association has been found between low neonatal T4 levels and an increased risk of impaired developmental outcome. Until now however, it is unclear whether T4 administration is required in preterm infants.Methods: We carried out a randomized, placebo-controlled, double-blind trial. 200 infants <30 weeks gestational age were enrolled. Administration of T4/placebo was started 12-24 hours after birth at a daily dose of 8 μg per kg birthweight per day and discontinued 6 weeks later. Neurological examinations were carried out at term, and at the corrected ages of 6, 12, and 24 months of age. Bayley developmental scales were performed at the latter 3 time points. Results: After the NICU-period 85 infants remained in the T4 group and 76 in the Placebo group. The 2 study groups did not differ with respect to birthweight, gestational age, sex, social and racial background, neonatal disease and cerebral hemorrhage and ischaemia. Mental nor psychomotor development differed between the 2 groups. At term age and at 24 months a significant reduction of abnormal neurological outcome was found in the T4 group (p=0.019 and 0.014 resp.). Also, a reduction of adverse outcome (death or an abnormal mental and neuromotor outcome) was found in the T4 group (RR 0.62, 95%-CI: 0.35-0.99). Conclusions: T4 administration to very preterm infants does not alter developmental outcome, but is associated with an improvement of neurological and adverse outcome at 24 months of age.

Screening en diagnostisch onderzoek van de cognitieve ontwikkelingsstoornissen en interventiemogelijkheden

SummaryCognitive functioning refers to the mental processes used by individuals to understand and adapt to the world surrounding them. Intelligence can be conceived as both outcome and measure of cognitive functioning. After a brief description of Piagets theory on cognitive development, several developmental and intelligence tests that can be used in the Netherlands are discussed. Next, specific considerations are made regarding testing of preterm children. Finally, possibilities for treatment and intervention in case of problems in cognitive development are described.SamenvattingCognitief functioneren betreft de mentale processen die mensen gebruiken om de wereld om hen heen te begrijpen en zich eraan aan te passen. Intelligentie kan worden beschouwd als uitkomst en maat van cognitief functioneren. Na een summiere beschrijving van de ideeën van Piaget over cognitieve ontwikkeling, worden de ontwikkelings- en intelligentietests besproken die in Nederland gebruikt worden. Vervolgens wordt aangegeven wat specifiek van belang is bij de afname van dergelijke tests bij ex-prematuren. Ten slotte wordt ingegaan op de interventiemogelijkheden wanneer een kind problemen in de cognitieve ontwikkeling ondervindt.