Search

Background There is an increasing number of adults with phenylketonuria ( PKU) on a low phenylalanine diet. In the general population, an increasing body mass index ( BMI) in the UK is a major problem with associated co-morbidities. The present study aimed to identify whether patients with diet-treated PKU have obesity rates comparable to those in the general population. Methods Two hundred and thirty-six PKU subjects (49% male, 51% female), aged >16 years, who were diagnosed by newborn screening and were receiving a low phenylalanine diet, were identified from seven metabolic centres in the UK. Retrospective data were collated on age, sex, BMI and mean phenylalanine concentration over the previous 12 months. Results Mean ( SD) phenylalanine concentration for all 236 subjects was 789 (311) μ m; mean ( SD) BMI was 26 (5.4) kg m−2 [males 25 (4.3) kg m−2, females 27 (6.2) kg m−2]; mean ( SD) age was 26 (7) years; and 55% had a BMI > 25 kg m−2. The percentage of subjects with a BMI >25 kg m−2 and >30 kg m−2, as well as increasing obesity with age, was similar to the UK population. A correlation was observed between increasing BMI and a higher phenylalanine concentration ( r = 0.243, P = 0.001). Conclusions The number of overweight and obese patients with diet-treated PKU in the UK is a concern. This could lead to other obesity-related complications increasing the complexity of diet and the cost of their care. There is a need to educate patients with respect to adopting a healthy, low phenylalanine diet and lifestyle to prevent further rises in BMI. [ABSTRACT FROM AUTHOR]

Adam S., Champion H., Daly A., Dawson S., Dixon M., Dunlop C., Eardley J., Evans S., Ferguson C., Jankowski C., Lowry S., MacDonald A., Maritz C., Micciche A., Robertson L., Stafford J., Terry A., Thom R., van Wyk K., Webster D., White F.J. & Wildgoose J. on behalf of the British Inherited Metabolic Diseases Group (BIMDG) Dietitian's Group. (2012) Dietary management of urea cycle disorders: UK practice. J Hum Nutr Diet. 25, 398-404 Abstract Background: There is no published data describing UK dietary management of urea cycle disorders (UCD). The present study describes dietary practices in UK inherited metabolic disorder (IMD) centres. Methods: Cross-sectional data from 16 IMD centres were collected by a questionnaire describing the management of UCD patients on prescribed protein-restricted diets. Results: One hundred and seventy-five patients [ N-acetylglutamate synthase deficiency, n = 3; carbamoyl phosphate synthase deficiency (CPS), n = 8; ornithine transcarbamoylase deficiency (OTC), n = 75; citrullinaemia, n = 41; argininosuccinic aciduria (ASA), n = 36; arginase deficiency, n = 12] were reported; 70% ( n = 123) aged 0-16 years; 30% ( n = 52) >16 years. Prescribed median protein intake decreased with age (0-6 months: 2 g kg−1 day−1; 7-12 months: 1.6 g kg−1 day−1; 1-10 years: 1.3 g kg−1 day−1; 11-16 years: 0.9 g kg−1 day−1 and >16 years: 0.8 g kg−1 day−1) with little variation between disorders. Adult protein prescription ranged 0.4-1.2 g kg−1 day−1 (40-60 g day−1). In the previous 2 years, 30% ( n = 53) were given essential amino acid supplements (EAAs) (CPS, n = 2; OTC, n = 20; citrullinaemia, n = 15; ASA, n = 7; arginase deficiency, n = 9). EAAs were prescribed for low plasma quantitative essential amino acids ( n = 13 centres); inadequate natural protein intake ( n = 11) and poor metabolic control ( n = 9). From diagnosis, one centre prescribed EAAs for all patients and one centre for severe defects only. Only 3% ( n = 6) were given branch chain amino acid supplements. Enteral feeding tubes were used by 25% ( n = 44) for feeds and 3% ( n = 6) for medications. Oral energy supplements were prescribed in 17% ( n = 30) of cases. Conclusions: In the UK, protein restriction based on World Health Organization 'safe intakes of protein', is the principle dietary treatment for UCD. EAA supplements are prescribed mainly on clinical need. Multicentre collaborative research is required to define optimal dietary treatments. [ABSTRACT FROM AUTHOR]