Diet therapy and metabolic control among Chilean adults with a neonatal diagnosis of Phenylketonuria

Abstract Phenylketonuria (PKU) is an autosomal recessive defect affecting the metabolic pathway of phenylalanine (Phe), causing hyperphenylalaninemia and neurotoxicity. Diagnosis must occur in the neonatal period and treatment should begin as early as possible. Evidence implies that treatment adherence declines as age advances. The aim was to describe the diet of a subgroup of Chilean adults with PKU currently in follow-up. Fifty-three subjects (49% women) followed up between January 2021 to April 2023 were considered. The concentration of Phe (PheC) in dried blood spots measured by fluorometry and 24-hour dietary recalls were analyzed. The median PheC of the sample was 438µmol/L (interquartile range(IQR):351-585µmol/L). A protein intake of 1.35±0.3 gr/Kg/d was observed of which 87% came from the protein substitute without Phe. Participants had a median Phe intake of 459mg/d (IQR:327-976) and 13.1g/d of fiber intake. Most participants, 51% and 92% reported consuming fruits and vegetables, respectively, and 32% consumed Low-Protein foods. Regarding micronutrients, all participants exceeded 90% adequacy according to recommendations. For vitamin-D and vitamin-B12, 100% is provided by the protein substitute. According to our results, it is mandatory to establish transition programs toward adulthood, to constantly maintain good metabolic control, and to adapt diet therapy to their new lifestyle.

Update on Dietary Compliance, Nutritional Status, and Neuropsychological Functioning in the Chilean Phenylketonuria cohort

Abstract Since 1992, Chile has had a Newborn Screening Program for Phenylketonuria (PKU), which currently has an incidence of 1:18,916 newborns. The objective of the current study was to describe the 2020 follow up of the Chilean PKU cohort. The variables analyzed were: nutritional status, dietary compliance and neuropsychological functioning. We conducted a descriptive cross-sectional statistical analysis. The 271 subjects with PKU had an average age of diagnosis of 17±8 days and a phenylalanine (Phe) level of 1122±546 umol/L. Approximately 80% of protein requirement came from a protein substitute. For those <18 years of age, 80% had good dietary compliance with Phe level between 120-360 umol/L and those >18 years had a median of 522 umol/L (95%CI 468 - 636). Forty-four percent of the active PKU cohort had overweight/obesity. Eighty-five percent of the cohort >4 years of age had a normal intelligence quotient (IQ) (score 80-120). We observed a negative correlation (p <0.001; 95% CI: - 0.5, -0.2) between IQ score and Phe level. The Chilean protocol and protein substitute subsidy for life, together with the follow-up and continuous education carried out by the clinical team has encouraged compliance.

Edulcorantes no nutritivos e ingesta diaria admisible en adultos y niños de peso normal y obesos de tres niveles socioeconómicos, y un grupo de diabéticos de la Región Metropolitana / Non-caloric sweeteners and daily acceptable intake in adults and children with normal weight and obesity from three different socioeconomic levels, and a diabetic group from Metropolitan Region

Introduction: There is wide availability of products containing sweeteners but there is no regulation on its consumption. Objective: To establish if adults and children with normal weight or obesity from three socioeconomic levels, and a group of adults and children with diabetes; do not exceed ADI levels for some sweeteners. Methods: Group 1 (477 adults, Group 2 (516 children) from socioeconomic levels: ABC1, C2 and C3, normal nutritional status and obesity, and group 3 (218) adults and children with diabetes. The daily intake of sweeteners was recorded, including: aspartame (ASP), acesulfame K (AK), cyclamate (CICL), saccharin (SAC), sucralose (SUC) and stevia (STV). Results: 85% adults and 75%% of children consumed products with sweeteners, and of these 50% were instant powdered beverages, soft drinks or diet yogurts. When comparing the consumption between groups 1 and 2, group 1 consumed a larger amount of sweeteners (p<0.05). Group 1 ABC1 ate more AK, ASP and SUC than C2 and C3 (p<0.05). Group 3 did not surpass the acceptable daily intake of AK, ASP, SUC and STE, but 5.8% of adults and 25% of diabetic children exceeded the ADI for SAC. Conclusions: The 97.5% and the 98.8% had a safe consumption of artificial sweeteners. It should be emphasized that 5.8% of adults and 25% of diabetic children exceeded the maximum ADI for SAC, finding that suggests to be continued long-term studies to elucidate whether this has implications for health.

Introducción: Existe gran disponibilidad de productos con edulcorantes pero no existe regulación sobre su consumo. Objetivo: determinar si individuos adultos y niños con estado nutricional normal u obesidad de tres niveles socioeconómicos y un grupo de adultos y niños con diabetes, no excedían la ingesta diaria admisible de los edulcorantes permitidos. Metodología: Grupo 1 (477 adultos) y grupo 2 (516 niños) de niveles socioeconómicos (NSE): ABC1, C2 y C3, estado nutricional normal y obesos, y grupo 3 (218) adultos y niños diabéticos. Se registró la ingesta diaria de edulcorantes incluyéndose: aspartame (ASP), acesulfamo K (AK), ciclamato (CICL), sacarina (SAC), sucralosa (SUC) y estevia (STV). Resultados: El 85 % adultos y 75 % de niños consumían productos con edulcorantes y de estos el 50% eran bebidas instantáneas en polvo, bebidas gaseosas o yogurts dietéticos. Al comparar la ingesta de edulcorantes entre los grupos 1 y 2, el grupo 1 tuvo una mayor ingesta (p<0.05) que el grupo 2. El grupo 1 del NSE ABC1, consumió mas AK, ASP y SUC que NSE C2 y C3 (p<0.05). En el grupo 3, el 5.8% de adultos y el 25% de niños diabéticos sobrepasaron el IDA sólo para SAC. Conclusiones: El 97.5% adultos y el 98.8% niños tuvieron ingesta dentro del nivel seguro en cada edulcorante. Se debe enfatizar que el 5,8% de adultos y 25% de niños diabéticos excedieron el IDA máximo para SAC, hallazgo que sugiere continuar con estudios a largo plazo que permitan dilucidar si esto tiene repercusión para la salud.

Fenilquetonuria e ingesta de selenio, zinc y vitamina E / Phenylketonuria and intake of selenium, zinc and vitamine E

La Fenilquetonuria (PKU) se produces por la deficiencia de la enzima Fenilalanina Hidroxilasa, causando un aumento plasmático de fenilalanina (FA). El objetivo del presente estudio fue evaluar la ingesta de Selenio (Se), Zinc (Zn) y vitamina E en niños PKU menores de 13 años de edad, que estaban en dieta restringida en FA y recibiendo fórmula especial sin FA. Método: Se incluyeron 50 PKU entre los 0 y 13 años y en control en el INTA, Universidad de Chile. Se analizó ingesta de vitamina E, Se y Zn, se midió nivel de FA en plasma y se evaluó estado nutritional. Resultados: Las recomendaciones diarias de Se y Zn se cubren en un 100 por ciento con la dieta habitual de PKU. Pero al excluir la formula sin FA, la cobertura de ambos nutriente disminuye a 45 por ciento y 20 por ciento respectivamente. La ingesta de vitamina E se cubre en forma natural por el consumo de aceites vegetales y al incluir la vitamina de la fórmula sin FA, la cobertura se incrementaba 5 veces sobre su recomendación. El nivel de FA en la sangre fue en promedio de 5.4 mg/dL, considerado un buen control metabólico. El 64 por ciento tenía un estado nutritional normal, el 30 por ciento estaba sobrepeso u obeso y un 6 por ciento riesgo de desnutrición. Conclusiones: Se concluye que la dieta de niños PKU cubre las recomendaciones de los micronutrientes: Zn, Se y vitamina E. No obstante se debe enfatizar la importancia que tiene la fórmula sin FA para cumplir con las recomendaciones nutricionales, especialmente de micronutrientes.

Phenylketonuria (PKU) is caused by a deficiency of the enzyme Phenylalanine Hydroxylase, resulting in increased plasma Phenylalanine (Phe). The aim of this study was to assess the intake of Selenium (Se), Zinc (Zn) and vitamin E in PKU children, who were on a diet restricted in Phenylalanine (Phe) and receiving a special formula without Phe. Method: the study included 50 PKU children between 0 and 13 years controled at INTA, University of Chile. We analyzed intake of vitamin E, Se and Zn, measured Phe plasma levels and assessed nutritional status. Results: The daily recommendations of Se and Zn were 100 percent covered with the usual PKU diet. By excluding the formula without Phe, the coverage of both nutrients decreased to 45 percent and 20 percent respectively. The intake of vitamin E was covered by the consumption of vegetable oils and when the formula without Phe was included, the coverage was increased 5 times over the recommended levels. Blood Phe level remained on average at 5.4 mgldL, considered a good metabolic control. Conclusions: We conclude that the diet of PKU children covered the recommended levels of Zn, Se and vitamin E. However, it should be emphasized the importance of the formula without Phe to meet nutritional recommendations, particularly of micronutrients.