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Behavioural factors related to metabolic control in patients with phenylketonuria

M R Crone1, F J van Spronsen, K Oudshoorn

  • 1TNO Prevention and Health, Leiden, The Netherlands. mr.crone@pg.tno.nl

Journal of Inherited Metabolic Disease
|September 10, 2005
PubMed

Insights

Parental attitudes and self-efficacy significantly impact dietary adherence in phenylketonuria (PKU). Addressing parental beliefs and challenges with protein substitutes is crucial for managing phenylalanine levels in PKU patients.

Area of Science:

  • Metabolic disorders
  • Genetics and heredity
  • Pediatric nutrition

Background:

  • Phenylketonuria (PKU) requires strict dietary management, primarily limiting phenylalanine (Phe) intake.
  • Parental factors may play a significant role in the dietary control of PKU patients.
  • Early and continuous treatment is essential for managing PKU outcomes.

Purpose of the Study:

  • To investigate the influence of parental factors on dietary control in early and continuously treated PKU patients.
  • To assess the relationship between parental attitudes, subjective norms, and self-efficacy and patient phenylalanine concentrations.
  • To identify key parental behaviors that can be modified to improve PKU dietary management.

Main Methods:

  • A questionnaire assessing parental attitudes, subjective norms, and self-efficacy was distributed to parents of 238 PKU patients.
  • Dietary control was evaluated based on mean phenylalanine (Phe) concentrations between 1994 and 1996.
  • Statistical analysis was performed to determine the association between parental factors and Phe levels.

Main Results:

  • Parents believing their child adheres well to the diet, despite occasional high Phe levels, had children with lower Phe concentrations (adjusted difference -103 micromol/L).
  • Higher Phe concentrations were observed when parents reported disapproval from relatives regarding dietary deviations (p = 0.004).
  • Difficulties in administering the synthetic protein substitute three times daily were associated with higher Phe concentrations (adjusted difference 156 micromol/L, p = 0.007).

Conclusions:

  • Parental attitudes and self-efficacy are strongly linked to dietary control in PKU.
  • Interventions should focus on supporting parents in consistently administering the protein substitute and adhering to the diet without excessive rigidity.
  • Modifiable parental factors offer potential targets for improving PKU management and patient outcomes.
Abstract

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