TY - JOUR
T1 - Protein intake and physical activity are associated with body composition in individuals with phenylalanine hydroxylase deficiency
AU - Jani, Rati
AU - Coakley, Kathryn
AU - Douglas, Teresa
AU - Singh, Rani
N1 - Funding Information:
The authors' report no conflict of interest beyond partial funding received from BioMarin for investigator-initiated research. Supported by the National Center for Advancing Translational Sciences of the National Institutes of Health under Award number UL1TR000454. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
Publisher Copyright:
© 2017 Elsevier Inc.
PY - 2017/6
Y1 - 2017/6
N2 - OBJECTIVE: Determine whether body composition as it relates to dietary protein in patients with phenylalanine hydroxylase (PAH) deficiency is associated with genotype, dietary factors, and lifestyle choices. METHODS: We examined associations between protein intake (intact and medical foods: MF) and body composition in PAH-deficient patients along with, physical activity, and genotype. Protein intakes (total, intact, and MF) were analysed from three-day food records with Nutrition Data System for Research (NDSR) in 59 children and 27 adults (N=86, median age=16.0years). The severity of PAH deficiency was classified using the genotype assigned value method (AV sum). Physical activity was assessed using a study-developed question (light vs. intense activity). Body composition was measured by DXA, including android:gynoid ratio (A:G), fat-free mass index (FFMI), fat mass index (FMI), and FMI:FFMI ratio.RESULTS: High intact protein intake was associated with high FFMI (rs=0.75, p=0.008) and low FMI:FFMI (rs=-0.59, p=0.04) in adults. Only in children, MF protein (rs=0.38, p=0.04) was directly proportional to FFMI. Median intact protein intakes of adults (25.1 vs. 9.9g/d, p<0.001) and children (11 vs. 6g/d, p<0.001) were higher than prescribed. Only in adults, the actual median MF protein intake was lower than prescribed (53 vs. 60g/d, p=0.03). In adults and children, light activity was associated with higher fat mass indices compared to intense activity (adults: FMI:FFMI: β=1.1, p=0.001, children: FMI:FFMI: β=1.1, p=0.007; FMI β=2.1, p=0.01; A:G β=1.1, p=0.04). All associations remained significant after covariate adjustment. Genotype was not associated with body composition. CONCLUSIONS: Although fat-free mass in adults was positively associated with intact protein intake, it should be consumed as prescribed per individual tolerance to maintain plasma Phe concentrations within treatment range. In children, total protein maximized with MF should be encouraged to promote lean mass. Nutrition counselling could be complemented with physical activity recommendations for optimal clinical outcomes.
AB - OBJECTIVE: Determine whether body composition as it relates to dietary protein in patients with phenylalanine hydroxylase (PAH) deficiency is associated with genotype, dietary factors, and lifestyle choices. METHODS: We examined associations between protein intake (intact and medical foods: MF) and body composition in PAH-deficient patients along with, physical activity, and genotype. Protein intakes (total, intact, and MF) were analysed from three-day food records with Nutrition Data System for Research (NDSR) in 59 children and 27 adults (N=86, median age=16.0years). The severity of PAH deficiency was classified using the genotype assigned value method (AV sum). Physical activity was assessed using a study-developed question (light vs. intense activity). Body composition was measured by DXA, including android:gynoid ratio (A:G), fat-free mass index (FFMI), fat mass index (FMI), and FMI:FFMI ratio.RESULTS: High intact protein intake was associated with high FFMI (rs=0.75, p=0.008) and low FMI:FFMI (rs=-0.59, p=0.04) in adults. Only in children, MF protein (rs=0.38, p=0.04) was directly proportional to FFMI. Median intact protein intakes of adults (25.1 vs. 9.9g/d, p<0.001) and children (11 vs. 6g/d, p<0.001) were higher than prescribed. Only in adults, the actual median MF protein intake was lower than prescribed (53 vs. 60g/d, p=0.03). In adults and children, light activity was associated with higher fat mass indices compared to intense activity (adults: FMI:FFMI: β=1.1, p=0.001, children: FMI:FFMI: β=1.1, p=0.007; FMI β=2.1, p=0.01; A:G β=1.1, p=0.04). All associations remained significant after covariate adjustment. Genotype was not associated with body composition. CONCLUSIONS: Although fat-free mass in adults was positively associated with intact protein intake, it should be consumed as prescribed per individual tolerance to maintain plasma Phe concentrations within treatment range. In children, total protein maximized with MF should be encouraged to promote lean mass. Nutrition counselling could be complemented with physical activity recommendations for optimal clinical outcomes.
KW - Body composition
KW - Genotype
KW - Intact protein
KW - Medical foods
KW - Phenylalanine hydroxylase deficiency
KW - Physical activity
UR - http://www.scopus.com/inward/record.url?scp=85018265040&partnerID=8YFLogxK
U2 - 10.1016/j.ymgme.2017.04.012
DO - 10.1016/j.ymgme.2017.04.012
M3 - Article
C2 - 28465125
SN - 1096-7192
VL - 121
SP - 104
EP - 110
JO - Molecular Genetics and Metabolism
JF - Molecular Genetics and Metabolism
IS - 2
ER -
