1
|
Pinto A, Daly A, Rocha JC, Ashmore C, Evans S, Ilgaz F, Hickson M, MacDonald A. Natural Protein Intake in Children with Phenylketonuria: Prescription vs. Actual Intakes. Nutrients 2023; 15:4903. [PMID: 38068761 PMCID: PMC10708375 DOI: 10.3390/nu15234903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2023] [Revised: 11/16/2023] [Accepted: 11/19/2023] [Indexed: 12/18/2023] Open
Abstract
In phenylketonuria (PKU), an important component of the UK dietary management system is a 50 mg phenylalanine (Phe)/1 g protein exchange system used to allocate the Phe/natural protein intakes according to individual patient tolerance. Any foods containing protein ≤ 0.5 g/100 g or fruits/vegetables containing Phe ≤ 75 mg/100 g are allowed without measurement or limit. In children with PKU, we aimed to assess the difference between the prescribed natural protein intake and their actual consumed intake, and to calculate the natural protein/Phe intake from foods given without measurement or restriction. Over a 6-month duration, three one-day diet diaries were collected every month by caregivers of children with PKU at the beginning of a follow-up study. Dietary intakes of Phe, as well as natural and total protein intakes, were calculated using Nutritics® (v5.09). Weekly blood Phe spots were collected by caregivers. The target blood Phe level was ≤360 μmol/L for ages up to 12 years and ≤600 μmol/L for ages ≥12 years. Sixteen early treated children (69% females) with PKU were recruited. The median age was 11 years (range: 9-13), and most had classical PKU (n = 14/16). A median of 18 (range 12-18) one-day diaries and 22 blood spots were analysed for each subject over 6 months. The median prescribed natural protein was 6 g/day (range: 3-27), but when calculated, the actual median intake from all foods consumed was 10 g/day (range: 4-37). The median prescribed Phe was 300 mg/day (range: 150-1350), but the actual median intake was 500 mg/day (range: 200-1850). The median difference between the prescribed and actual natural protein daily intakes was +4 g/day (range: -2.5 to +11.5), with a median percentage increase of 40% for natural protein/Phe intake (p < 0.001). The median blood Phe level was 250 μmol/L (range 20-750), with 91% of blood Phe levels within the target range. Only one patient (11 years) had less than 75% of their blood Phe levels within the target range. The UK Phe exchange system provides flexibility in the dietary management of PKU. With this method, the actual natural protein intake was 167% higher than the prescribed amount. Although this led to a variable daily protein intake, the majority of children (n = 15/16) experienced no deterioration in their metabolic control.
Collapse
Affiliation(s)
- Alex Pinto
- Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (A.D.); (C.A.); (S.E.); (F.I.); (A.M.)
- Plymouth Institute of Health and Care Research, Faculty of Health, University of Plymouth, Plymouth PL6 8BH, UK;
| | - Anne Daly
- Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (A.D.); (C.A.); (S.E.); (F.I.); (A.M.)
| | - Júlio César Rocha
- Nutrition and Metabolism, NOVA Medical School (NMS), Faculdade de Ciências Médicas (FCM), Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal;
- CINTESIS@RISE, Nutrition and Metabolism, NOVA Medical School (NMS), Faculdade de Ciências Médicas, (FCM), Universidade NOVA de Lisboa, 1169-056 Lisboa, Portugal
- Reference Centre of Inherited Metabolic Diseases, Centro Hospitalar Universitario de Lisboa Central, 1169-045 Lisboa, Portugal
| | - Catherine Ashmore
- Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (A.D.); (C.A.); (S.E.); (F.I.); (A.M.)
| | - Sharon Evans
- Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (A.D.); (C.A.); (S.E.); (F.I.); (A.M.)
| | - Fatma Ilgaz
- Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (A.D.); (C.A.); (S.E.); (F.I.); (A.M.)
- Department of Nutrition and Dietetics, Faculty of Health Sciences, Hacettepe University, 06100 Ankara, Turkey
| | - Mary Hickson
- Plymouth Institute of Health and Care Research, Faculty of Health, University of Plymouth, Plymouth PL6 8BH, UK;
| | - Anita MacDonald
- Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (A.D.); (C.A.); (S.E.); (F.I.); (A.M.)
- Plymouth Institute of Health and Care Research, Faculty of Health, University of Plymouth, Plymouth PL6 8BH, UK;
| |
Collapse
|
2
|
Pinto A, Ilgaz F, Evans S, van Dam E, Rocha JC, Karabulut E, Hickson M, Daly A, MacDonald A. Phenylalanine Tolerance over Time in Phenylketonuria: A Systematic Review and Meta-Analysis. Nutrients 2023; 15:3506. [PMID: 37630696 PMCID: PMC10458574 DOI: 10.3390/nu15163506] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Revised: 07/29/2023] [Accepted: 08/03/2023] [Indexed: 08/27/2023] Open
Abstract
In phenylketonuria (PKU), natural protein tolerance is defined as the maximum natural protein intake maintaining a blood phenylalanine (Phe) concentration within a target therapeutic range. Tolerance is affected by several factors, and it may differ throughout a person's lifespan. Data on lifelong Phe/natural protein tolerance are limited and mostly reported in studies with low subject numbers. This systematic review aimed to investigate how Phe/natural protein tolerance changes from birth to adulthood in well-controlled patients with PKU on a Phe-restricted diet. Five electronic databases were searched for articles published until July 2020. From a total of 1334 results, 37 articles met the eligibility criteria (n = 2464 patients), and 18 were included in the meta-analysis. The mean Phe (mg/day) and natural protein (g/day) intake gradually increased from birth until 6 y (at the age of 6 months, the mean Phe intake was 267 mg/day, and natural protein intake was 5.4 g/day; at the age of 5 y, the mean Phe intake was 377 mg/day, and the natural protein intake was 8.9 g/day). However, an increase in Phe/natural protein tolerance was more apparent at the beginning of late childhood and was >1.5-fold that of the Phe tolerance in early childhood. During the pubertal growth spurt, the mean natural protein/Phe tolerance was approximately three times higher than in the first year of life, reaching a mean Phe intake of 709 mg/day and a mean natural protein intake of 18 g/day. Post adolescence, a pooled analysis could only be performed for natural protein intake. The mean natural protein tolerance reached its highest (32.4 g/day) point at the age of 17 y and remained consistent (31.6 g/day) in adulthood, but limited data were available. The results of the meta-analysis showed that Phe/natural protein tolerance (expressed as mg or g per day) increases with age, particularly at the beginning of puberty, and reaches its highest level at the end of adolescence. This needs to be interpreted with caution as limited data were available in adult patients. There was also a high degree of heterogeneity between studies due to differences in sample size, the severity of PKU, and target therapeutic levels for blood Phe control.
Collapse
Affiliation(s)
- Alex Pinto
- Department of Dietetics, Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (S.E.); (A.D.); (A.M.)
- School of Health Professions, Faculty of Health, University of Plymouth, Plymouth PL4 6AB, UK;
| | - Fatma Ilgaz
- Department of Nutrition and Dietetics, Faculty of Health Sciences, Hacettepe University, 06100 Ankara, Turkey;
| | - Sharon Evans
- Department of Dietetics, Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (S.E.); (A.D.); (A.M.)
| | - Esther van Dam
- Beatrix Children’s Hospital, University of Groningen, University Medical Center, 9700 RB Groningen, The Netherlands;
| | - Júlio César Rocha
- Nutrition and Metabolism, NOVA Medical School, Faculdade de Ciencias Medicas, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal;
- CINTESIS@RISE, NOVA Medical School, Faculdade de Ciências Médicas, NMS, FCM, Universidade Nova de Lisboa, 1169-056 Lisboa, Portugal
- Reference Centre of Inherited Metabolic Diseases, Centro Hospitalar Universitario de Lisboa Central, 1169-045 Lisboa, Portugal
| | - Erdem Karabulut
- Department of Biostatistics, Faculty of Medicine, Hacettepe University, 06100 Ankara, Turkey;
| | - Mary Hickson
- School of Health Professions, Faculty of Health, University of Plymouth, Plymouth PL4 6AB, UK;
| | - Anne Daly
- Department of Dietetics, Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (S.E.); (A.D.); (A.M.)
| | - Anita MacDonald
- Department of Dietetics, Birmingham Women’s and Children’s Hospital, Birmingham B4 6NH, UK; (S.E.); (A.D.); (A.M.)
| |
Collapse
|
3
|
Efficacy of a New Low-Protein Multimedia Diet App for PKU. Nutrients 2022; 14:nu14112182. [PMID: 35683982 PMCID: PMC9182776 DOI: 10.3390/nu14112182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 05/17/2022] [Accepted: 05/21/2022] [Indexed: 02/01/2023] Open
Abstract
Patients with phenylketonuria (PKU) require a phenylalanine/protein-restricted diet, with limited food choice. Interpreting food labels, calculating protein intake, and determining food suitability are complex and confusing tasks. A mobile multi-media low-protein diet app was developed to guide food choice, label interpretation, and protein calculation. ‘PKU Bite’® includes >1100 specialist and regular low-protein foods, is colour-coded for suitability, and features a protein calculator. A 12-week randomised controlled trial assessed app efficacy, compared with written/pictorial material, in 60 parents/caregivers of children with PKU, aged 1−16 years, and 21 adolescents with PKU. Questionnaires examined self-efficacy and label-reading knowledge; food records evaluated natural-protein intake, compared with prescriptions. There was no difference between groups in label-reading knowledge or self-efficacy, but there was a trend for improved accuracy of dietary protein calculation, when using the app (baseline/12-weeks: app 35%/48%; control 39%/35%). Parents of children <10 years of age (median 5.5 years), were most likely to use the app to check the phenylalanine/protein content of a food or to verify suitability of foods. Whilst the app was popular (43%), so too was contacting the dietitian (43%), using written/pictorial information (24%), or using social media (18%). This is the first dietary app for PKU to be studied in a systematic way as well as validated by healthcare professionals. It is a useful adjunct to existing resources and will be a valuable tool for educating parents of younger children.
Collapse
|