Navigating adulthood with PKU: metabolic outcomes, quality of life, and mental health 4.5 years post-transition.

Mean phenylalanine concentration remained stable over 4.5 years after transition into adult care.

• Study included 45 adults with PKU assessed 4.5 years after entering adult care.
• Mean Phe concentration was 998.3 ± 290.4 µmol/l.
• This was a retrospective study using venous blood samples and dried blood spots to assess Phe concentrations.
• Data from transition and annual follow-ups were analyzed.

Adherence to low-protein diet and amino acid mixture (AAM) intake both increased over the 4.5-year follow-up period.

• Adherence to low-protein diet increased from 77.8% to 100% over 4.5 years.
• AAM intake increased from 62.5% to 85.8% over the same period.
• Dietary habits and AAM intake were recorded via interviews.

Consistent AAM use and adherence to a low-protein diet were each associated with significantly lower phenylalanine levels.

• Consistent AAM use (≥3x/day) was associated with Phe levels lower by 362.9 µmol/l compared to no AAM use (p < 0.05).
• Adherence to low-protein diet was associated with Phe levels lower by 304.1 µmol/l compared to no diet adherence (p < 0.05).

The large majority of adults with PKU had comorbidities, with psychiatric disorders being the most common.

• Overall, 89% of the 45 adults had comorbidities.
• Psychiatric disorders were the most commonly reported comorbidity, present in 31% of participants.
• Comorbidities were obtained from medical records.

Adults with PKU and psychiatric comorbidities had significantly higher phenylalanine levels compared to those without psychiatric comorbidities.

• Mean Phe levels were 1169 µmol/l in those with psychiatric comorbidities versus 823 µmol/l in those without (p < 0.05).
• Those with psychiatric comorbidities also showed lower dietary adherence (33% vs. 70%, p < 0.01).
• Greater quality of life impairment was also observed in those with psychiatric comorbidities.

Quality of life and well-being were measured using the PKU-QOL and WHO-5 instruments.

• The PKU-QOL was scored 0–100, with lower scores indicating better QoL.
• The WHO-5 was scored 0–25, with higher scores indicating better well-being.
• Individuals with psychiatric comorbidities showed greater QoL impairment on these measures compared to those without psychiatric comorbidities.