Cognitive Functioning in Phenylketonuria: A Lifespan Perspective

Stephan Huijbregts1, Cristina Romani2

  • 1Education and Child Studies, Leiden Institute for Brain and Cognition, Leiden University, 2333 AK Leiden, The Netherlands.

Nutrients
|January 10, 2026
PubMed

Insights

Phenylketonuria (PKU) research needs more studies on young children and older adults. Understanding cognitive function in these PKU patients is crucial for development and aging.

Area of Science:

  • Metabolic disorders
  • Neuroscience
  • Developmental psychology

Background:

  • Phenylketonuria (PKU) is an inherited metabolic disorder.
  • It causes phenylalanine buildup, leading to cognitive impairment.
  • Current research on PKU cognitive outcomes primarily focuses on school-aged children, adolescents, and young adults.

Purpose of the Study:

  • To highlight the need for research on cognitive functioning in very young and older individuals with PKU.
  • To emphasize the importance of early cognitive development for long-term outcomes.
  • To explore the potential impact of PKU and metabolic control on age-related cognitive decline.

Main Methods:

  • This is a review article.
  • It synthesizes existing literature on PKU and cognitive function.
  • It identifies gaps in current research.

Main Results:

  • There is a lack of studies on the cognitive functioning of very young and older PKU patients.
  • Early cognitive development is critical for later cognitive and behavioral functioning.
  • Metabolic control in PKU may influence age-related cognitive decline.

Conclusions:

  • Further research is essential to understand cognitive development and aging in individuals with PKU.
  • Investigating cognitive function across the lifespan in PKU is crucial for comprehensive patient care.
  • Addressing research gaps will inform interventions and improve long-term outcomes for PKU patients.

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