Evaluation of factors affecting the success of follow-up and treatment of adults diagnosed with phenylketonuria by newborn screening

Background: Phenylketonuria (PKU) is an autosomal recessive congenital metabolic disease characterized by phenylalanine hydroxylase enzyme deficiency. It is treated with a lifelong low phenylalanine diet. Returning non-diet adults to diet is of great importance in terms of cognitive functions. It is aimed to return patients who have lost follow-up to diet by evaluating the factors affecting the success of follow-up and treatment in adults with phenylketonuria and developing strategies in this regard. Materials and Method: File information of adult phenylketonuria patients between April and July 2021 in the Department of Nutrition and Metabolism, Department of Pediatrics, Istanbul Faculty of Medicine, was reviewed. "Adult Attention Deficit Hyperactivity Disorder Self-Report Scale" and Phenylketonuria Quality of Life Questionnaire were applied. Results: The mean age of the patient group, of which 50.0% (n=67) was female and 50.0% (n=67) was male; it is 23.25±2.95. 68.7% is Classical Phenylketonuria. 82.1% of them did not have special learning difficulties. Of the patients, 30.3% (n=60) were lost to follow-up and 79.9% lived in Istanbul. 72.4% were found to manage the diet themselves. The families of 58.2% have attended previous trainings. 83% of them are professionals or undergraduate students. There was no statistically significant difference in the success of follow-up and treatment according to the age at diagnosis, place of residence , length of work, participation of families in trainings, family education status, problems that may be experienced under insurance and Adult Attention Deficit Hyperactivity Disorder Scale. Those with a classic diagnosis showed higher follow-up success than those with a mild diagnosis. Patients who managed the diet themselves showed higher follow-up and treatment success than the others. According to the Pku Diet and Your Medical Formula and Daily Life with Pku sub-dimensions of the Phenylketonuria Quality of Life Scale, a statistically significant negative correlation was observed between the mean of follow-up and treatment success in the last 5 years. Conclusion: The success of follow-up and treatment can be increased by making the patients' diet management themselves, providing them with information about different treatment options, facilitating the implementation of the diet, and reducing the effect of the disease that the patients feel in their daily life.