Avaliação da qualidade de vida e sua associação com a adesão ao tratamento em pacientes com fenilcetonúria no Distrito Federal

Abstract

Introduction: Phenylketonuria (PKU) is a rare, autosomal recessive disease characterized by accumulation of the amino acid phenylalanine (Phe) in the blood and other tissues. The basis of the treatment of phenylketonuria consists of a diet restricted in natural proteins, as this amino acid has a preponderant presence in foods with a high protein content. Therefore, legumes, most cereals and foods rich in protein with high biological value content should be excluded from the diet. It is also necessary to ingest a free-phe complement of amino acids, special low-protein foods and natural foods with little phenylalanine. A low-Phe diet throughout life impairs quality of life, especially in adolescents and adults, who assume responsibility for diet and follow-up from their parents and expect autonomy and freedom in their daily routine. Adherence to dietary treatment in patients with PKU, according to the literature, deteriorates with increasing age, being unsatisfactory in adolescents and adults. Thus, studies that associate quality of life and adherence to treatment are scarce and opportune. Objectives: The aim of the study was to examine the health-related quality of life (HRQoL) of patients with Phenylketonuria (PKU) using PKU-QOL questionnaires, investigating their correlation with adherence to treatment. Methods: This is a cross-sectional, prospective, single-center, non- interventional study with 51 patients of different age groups using a phenylalanine- free metabolic formula. The PKU-QOL questionnaires, composed of the modules Symptoms, PKU in general, Phe-free amino acid supplement administration and Dietary protein restriction, three indicators of adherence to treatment (the average of the median Phe for the four-year period (2018-2021), the current concentration of Phe in the week the questionnaire was completed (measured 3 days before the routine outpatient visit) and the median of the collection of tests and consultations for the quadrennium (2018-2021)) and self-assessed general health status were used in the assessment. Data collection was carried out at the Reference Center for Rare Diseases of the Hospital de Apoio de Brasília - HAB, from December 2021 to August 2022. Data were analyzed using non-parametric tests (Kruskal Wallis One-Way Test and Test U of Mann-Whitney), according to the results of normality tests. Results: The final sample consisted of 51 patients. Children, adolescents, and adults had percentages of overall adherence to treatment of 62.5%, 63.6% and 18.8%, respectively. Significant correlations between PKU-QOL scores and adherence were observed across age groups and domains, among adult respondents, there was a positive and robust correlation between the "self-rated health status" score and the domains Anxiety - Phe levels (p=0.019, rs=0.719), Financial impact of PKU (p =0.045, rs= 0.642), Overall difficulty following dietary protein restriction (p=0.030, rs =0.682). Among adolescents, there was a positive correlation and strong between the Self-rated status Health score and various symptom domains, the highest coefficients were found for Lack of concentration (p=0.002, rs=0.820), Slow thinking (p=0.003, rs=0.803), Anxiety (p= 0.002, rs= 0.820), Emotional impact of PKU (p =0.001, rs=0.833), Social impact of PKU (p = 0.005, rs= 0.777), Overall impact of PKU (p= 0.016, rs= 0.700) , Adherence to supplements (p= 0.031, rs= 0.647), Social impact of dietary protein restriction (p= 0.004, rs= 0.787), Overall impact of dietary protein restriction (p= 0.035, rs= 0.638) , Food enjoyment (p= 0.004, rs= 0.793), suggesting a worse perception of health status; as well as an emotional, social and general impact of the disease, a social and general impact of protein restriction in the diet and greater difficulty in adhering to the metabolic formula in the analyzed period. The Symptoms module obtained median scores classified as mild to moderate; PKU in general achieved high impact scores for Emotional Impact of PKU, Practical Impact of PKU, Impact of child anxiety – blood test, Anxiety – blood Phe levels, and Anxiety - Blood Phe Levels During Pregnancy; in the Phe-free amino acid supplement administration, the Guilt if poor adherence to supplements domain obtained scores of major or severe impact in all age groups, except in children. In the module, Dietary protein restriction, in the Guilt if Dietary Protein Restriction not followed, there were scores of major or severe impact in all age groups, except in children. Products developed: the original articles entitled: “ADDIE methodology for the construction of an educational health product for phenylketonuria” and “Quality of life and adherence to treatment in patients with phenylketonuria in the Federal District.”; from the review article: Quality of life in adults with phenylketonuria: a systematic review”. Presentation at congresses: ADDIE methodology for the construction of an educational health product for phenylketonuria” at the 13th Brazilian Congress of Product Development Management held – CBGDP/2021, “Metabolic control and overweight in the adult phenylketonuric population of the DF: how is the outpatient follow-up?” at the XI National Forum of Professional Masters and Doctorates in Nursing - FOPRENF/2021 and "How is adherence to treatment and the quality of life of PKU patients in the Federal District?" at the 34th CBGM, 9th CBTEIM, 7th CBSBEGG, held in São Paulo - SP. Publication of the book (Ebook) entitled: "Phenylketonuria in adults: questions and answers" and the book (Ebook) entitled: "Nutritional Education Booklet for Phenylketonuria" both by Publisher Coleta Científica. Conclusions: Adherence to treatment in phenylketonuria negatively affected HRQoL in the sample studied, with a worse perception of health status, significant emotional, social and general repercussions of the disease and its treatment, and great difficulty in adhering to protein supplementation without phenylalanine. This may be related to the methodology used, but also to a reality of treatment resources different from that presented in European countries and the United States. In Brazil, there is no availability of protein supplements with low or phenylalanine-free content with better palatability, offer of special low-protein processed foods in a subsidized way, offer of sapropterin in an expanded form for all responders. In this context, the products of this research project are innovative and have the potential to influence public policies and clinical practice, as they aim to improve adherence through nutritional education. The technical production developed has applicability and potential to generate national impact, since more treatment resources and vigorous work on food and nutrition education in phenylketonuria are needed. The challenges associated with the treatment of CNF must have effective interventions for the well-being and better health of this population.