Related Experiment Videos
[Intellectual development of patients with phenylketonuria; 15-year national screening in The Netherlands]
J Huisman1, L W van der Schot, M M Hendrikx
1Academisch Ziekenhuis Vrije Universiteit, afd. Medische Psychologie, Amsterdam.
Insights
Phenylketonuria (PKU) and hyperphenylalaninaemia (HPA) patients show normal intellectual development until age 8. Older PKU patients may experience declining IQ scores, necessitating further research into long-term cognitive effects.
Area of Science:
- Metabolic disorders
- Neurodevelopmental disorders
- Genetics
Context:
- Neonatal screening for PKU and HPA initiated in the Netherlands in 1974.
- Longitudinal study tracking intellectual development.
- Involves 116 patients (101 PKU, 15 HPA) detected and treated within the first 15 years of screening.
Purpose:
- To evaluate the intellectual development of patients with phenylketonuria (PKU) or hyperphenylalaninaemia (HPA).
- Assess cognitive functioning across different age groups.
- Identify potential sex-related differences in cognitive performance.
Summary:
- Intellectual functioning in PKU and HPA patients aligns with test norms until approximately 8.5 years of age.
- A trend towards lower IQ scores is observed in older PKU patients.
- No significant sex differences in mental functioning were found among PKU patients.
Impact:
- Highlights the need for continued monitoring of cognitive development in PKU patients, particularly in older age groups.
- Suggests potential long-term neurocognitive effects of PKU that warrant further investigation.
- Informs clinical management and follow-up strategies for individuals with PKU and HPA.
Objective:
To evaluate the intellectual development of patients with phenylketonuria (PKU) or hyperphenylalaninaemia (HPA).
Design:
Longitudinal follow-up study.
Setting:
University Children's Hospitals of Amsterdam, Groningen, Nijmegen, and Rotterdam.
Methods:
In September 1974 a nationwide neonatal screening for PKU started in the Netherlands. We obtained data on the intellectual development of 116 patients (101 classical PKU, 15 HPA), all detected and treated in the first 15 years of this screening. The children were tested at 6 ages with different instruments for the assessment of intellectual functions, and the scores were compared with the test norms. Performance and verbal capacities were determined as well as possible sex-related differences.
Results:
Our data show that the levels of intellectual functioning of PKU and HPA patients do not differ from test norms until the age of 8 yr 6 months. In the older PKU patients there appears to be a trend towards lower IQ scores. We found no sex differences in the mental functioning of PKU patients.
Conclusion:
Continuation of this study is necessary in order to investigate possible negative effects of PKU on cognitive functioning, especially in the older age groups.