Randomised controlled trial of essential fatty acid supplementation in phenylketonuria.
OBJECTIVE
The long-chain polyunsaturated fatty acids (LC-PUFA) status of children with PKU is often compromised. LC-PUFA, which are important fatty acids in the development of the CNS, can be synthesised endogenously from the parent essential fatty acids (EFA) provided dietary intakes are adequate. This study was designed to assess the biochemical effect over a 20-week period of a phe-free protein substitute that has been supplemented with a balanced blend of n-3 and n-6 EFAs on LC-PUFA status of children with PKU.


METHODS
Fifty three community-living children aged 1-10 years diagnosed with PKU in the newborn period were recruited from seven tertiary centres in the UK and France and randomised to a fat-free control formula or the EFA-supplemented test-treatment formula in an open, prospective study. Forty four children completed the study (20 controls, 24 test-treatments). Fatty acid status was assessed at entry and 20-weeks follow-up. Three day dietary diaries were recorded at 20 weeks' follow-up. The safety, efficacy and palatability of the test-treatment formula were also assessed.


RESULTS
The test-treatment group had significantly higher intakes of fat and EFA than the control group. There was a significant between group difference (P=0.04) in increases in median docosahexaenoic acid (DHA) concentrations in erythrocyte phospholipids, which increased by 19% in the test-treatment group and by 0.5% in the control group over the study period. Growth and phe control were satisfactory in all subjects.


CONCLUSIONS
Supplementing the diets of children with PKU with a balanced blend of n-6 and n-3 EFA improves DHA status without compromising AA status.
Cleary
M A
MA
Department of Metabolic Medicine, Great Ormond St. Hospital for Sick Children, London, UK. Clearm@gosh.nhs.uk
Feillet
F
F
White
F J
FJ
Vidailhet
M
M
Macdonald
A
A
Grimsley
A
A
Maurin
N
N
de Baulny
H Ogier
HO
Rutherford
P J
PJ
D002648:Child; D002675:Child, Preschool; D019587:Dietary Supplements; D004912:Erythrocytes / Q000737:chemistry*; D005228:Fatty Acids, Essential / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D005260:Female; D006128:Growth / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D007223:Infant; D008297:Male; D009752:Nutritional Status; D010649:Phenylalanine / Q000097:blood; D010661:Phenylketonurias / Q000097:blood / Q000188:drug therapy*; D011446:Prospective Studies; D016896:Treatment Outcome
D005228:Fatty Acids, Essential; D010649:Phenylalanine