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Published on: August 25, 2014
Neurodevelopmental outcome in extremely low birth weight infants: what is the minimum age for reliable developmental
Wolfgang Voss1, Achim-Peter Neubauer, Michael Wachtendorf
1Sozialpädiatrisches Zentrum, Hannover, Germany. voss@hka.de
Insights
Reliable neurodevelopmental prognosis for extremely low birth weight infants requires follow-up until at least 6 years of age. Early assessments, even at 3 years corrected age, may not accurately predict outcomes for these vulnerable children.
Area of Science:
- Neonatal Medicine
- Developmental Pediatrics
- Neuroscience
Background:
- Extremely low birth weight (ELBW) infants (<1000 g) face significant neurodevelopmental challenges.
- Establishing reliable developmental prognoses for ELBW infants is crucial for timely intervention.
- Current follow-up protocols may not adequately capture the long-term neurodevelopmental trajectory of ELBW survivors.
Purpose of the Study:
- To determine the optimal age for providing a reliable neurodevelopmental prognosis in extremely low birth weight infants.
- To evaluate the accuracy of developmental assessments at various corrected ages in ELBW children.
- To establish the minimum follow-up duration needed for dependable neurodevelopmental outcome statements in ELBW infants.
Main Methods:
- Longitudinal follow-up of 129 ELBW infants (median birth weight 794 g, gestational age 27.0 weeks).
- Neurodevelopmental and psychometric testing conducted up to 6–10 years of age (mean 8.5 years).
- Classification of developmental status into major impairment, minor impairment, and normal development for children without cerebral palsy.
Main Results:
- At final follow-up, 17% had major impairment (9% cerebral palsy), 42% minor impairment, and 41% normal development.
- Developmental prognosis accuracy was 49% at term, 59% at 12 months corrected age, and 70% at 3 years corrected age.
- Cerebral palsy diagnosis was reliably confirmed by 2 years corrected age.
Conclusions:
- Reliable neurodevelopmental assessment of ELBW infants necessitates a follow-up period of at least 6 years.
- Follow-up testing before 6 years may yield unreliable developmental prognoses for ELBW infants.
- Cerebral palsy can be diagnosed reliably by 2 years corrected age, but broader neurodevelopmental outcomes require longer observation.
Aim:
We present a longitudinal study on the neurodevelopmental outcome in preterm infants with extremely low birth weight <1000 g (ELBW) to answer the question at which age a developmental prognosis can be given.
Methods:
A group of 129 ELBW, median birth weight: 794 g (SD 123 g), gestational age: 27.0 weeks (SD 2.0 weeks), born between 1993 and 1998, were followed up to the age between 6 and 10 years (mean 8.5 years [SD 1.7 years]) and evaluated by neurodevelopmental and psychometric tests. The status of children without cerebral palsy was ranked into categories of major, minor and no developmental impairments.
Results:
At the time of the last follow-up examination 17% of the children showed a major impairment including 9% cerebral palsy, 42% a minor impairment and 41% were normally developed. The longitudinal analysis of cases without cerebral palsy reveals that an assessment 'at term' can only give the correct developmental prognosis in 49% of the cases. At the corrected age of 12 months the prognosis is correct in 59% of the cases, whereas at the corrected age of 3 years 70% proves to be right. Diagnosis of cerebral palsy could be confirmed at the corrected age of 2 years with sufficient reliability.
Conclusion:
The neurodevelopmental evaluation of former preterm infants with a birth weight <1000 g demands a follow-up period of at least 6 years in order to make reliable statements. We are doubtful that follow-up testing completed prior to this age can yield reliable results.
