Liemburg et al. (2015) explored if the Behavior Rating Inventory of Executive Function (BRIEF) instrument is sufficient to monitor for Executive Function (EF) deficits in patients with PKU.
55 adult PKU patients (mean age 28.3 ± 6.2 years) filled out the BRIEF-A questionnaire and performed computerized tasks measuring executive functions (inhibition, cognitive flexibility, and working memory). The outcome of the BRIEF-A questionnaire was compared with the neurocognitive outcome as measured by three tasks from the Amsterdam Neuropsychological Tasks (ANT).
BRIEF-A results: 42% of the PKU patients scored in the borderline/clinical range; 11% scored >1 SD above the normative mean (higher being poorer score).
ANT results: 34-36% of patients showed deficits in inhibitory control; 31-24% showed deficits in cognitive flexibility, as compared to the general Dutch population.
No significant correlations between the two methods were found, which was confirmed with the Bland-Altman approach where no agreement between the two methods was observed.
The study concludes that patients reporting EF problems in daily life are not necessarily those that present with core EF deficits and that BRIEF-A is not a sufficient way to monitor EF in adult PKU patients.
Is BRIEF a useful instrument in day to day care of patients with phenylketonuria? Liemburg GB, Jahja R, van Spronsen FJ, de Sonneville LM, van der Meere JJ, Bosch AM, Hollak CE, Rubio-Gozalbo ME, Brouwers MC, Hofstede FC, de Vries MC, Janssen MC, van der Ploeg AT, Langendonk JG, Huijbregts SC. Mol Genet Metab. 2015 Mar;114(3):425-30. PMID: 25541101
Posted by Yannis Trakadis, MD