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Neurocognitive functioning in adults with phenylketonuria: results of a long term study

J Weglage1, J Fromm, A van Teeffelen-Heithoff

  • 1University of Münster, Department of Pediatrics, Albert-Schweitzer-Campus 1, 48149 Münster, Germany.

Molecular Genetics and Metabolism
|September 28, 2013
PubMed

Insights

Cognitive performance in early-treated phenylketonuria (PKU) patients remained stable over five years. However, adult PKU patients, especially older ones, show neurocognitive impairments linked to childhood phenylalanine levels, underscoring the importance of adolescent dietary adherence.

Area of Science:

  • Neuroscience
  • Genetics
  • Metabolic Disorders

Background:

  • Phenylketonuria (PKU) is a rare genetic disorder requiring early treatment.
  • Long-term neurological and neuropsychological outcomes in early-treated PKU require further investigation.

Purpose of the Study:

  • To assess neurological and neuropsychological performance in adult patients with early-treated PKU.
  • To evaluate cognitive changes over a five-year period in this cohort.

Main Methods:

  • A controlled study of 57 early-treated PKU patients (aged 19-41) and 46 healthy controls.
  • Assessments included IQ, attention, and information processing, with brain MRI. Follow-up occurred after five years.

Main Results:

  • Cognitive functions remained stable in both PKU patients and controls over five years.
  • PKU patients consistently showed lower IQ scores than controls.
  • Older PKU patients (>32 years) exhibited poorer information processing and attention, correlating with higher childhood/adolescent phenylalanine (Phe) levels.

Conclusions:

  • Cognitive performance in early-treated PKU does not deteriorate significantly over a five-year interval in adulthood.
  • Neurocognitive impairment is present in adult PKU patients, particularly older individuals.
  • Adolescent dietary control is crucial, as early diet relaxation may contribute to observed impairments.
Abstract

Keywords:
AdolescenceAttentionHPAHPLCIQImagingInformation processingMRIPKUPheSDSustained Attention TestWAIS IIIWechsler Adult Intelligence ScaleWhite matter alterationsZVTZahlen-Verbindungs-Testd2high-performance liquid chromatographyhyperphenylalaninemiaintelligence quotientmagnetic resonance imagingphenylalaninephenylketonuriastandard deviation

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