A three-year longitudinal study comparing bone mass, density, and geometry measured by DXA, pQCT, and bone turnover markers in children with PKU taking L-amino acid or glycomacropeptide protein substitutes

Daly, Anne, Högler, Wolfgang, Crabtree, Nicola, Shaw, Nick, Evans, Sharon, Pinto, Alex, Jackson, Richard, Ashmore, Catherine, Rocha, Júlio C., Strauss, Boyd J., Wilcox, Gisela, Fraser, William D., Tang, Jonathan C. Y. and MacDonald, Anita (2021) A three-year longitudinal study comparing bone mass, density, and geometry measured by DXA, pQCT, and bone turnover markers in children with PKU taking L-amino acid or glycomacropeptide protein substitutes. Nutrients, 13 (6). ISSN 2072-6643

[img] PDF (nutrients-13-02075-v3) - Published Version
Available under License Creative Commons Attribution.

Download (2MB)

Abstract

In patients with phenylketonuria (PKU), treated by diet therapy only, evidence suggests that areal bone mineral density (BMDa) is within the normal clinical reference range but is below the population norm. Aims: To study longitudinal bone density, mass, and geometry over 36 months in children with PKU taking either amino acid (L-AA) or casein glycomacropeptide substitutes (CGMP-AA) as their main protein source. Methodology: A total of 48 subjects completed the study, 19 subjects in the L-AA group (median age 11.1, range 5–6 years) and 29 subjects in the CGMP-AA group (median age 8.3, range 5–16years). The CGMP-AA was further divided into two groups, CGMP100 (median age 9.2, range 5–16years) (n = 13), children taking CGMP-AA only and CGMP50 (median age 7.3, range 5–15years) (n = 16), children taking a combination of CGMP-AA and L-AA. Dual X-ray absorptiometry (DXA) was measured at enrolment and 36 months, peripheral quantitative computer tomography (pQCT) at 36 months only, and serum blood and urine bone turnover markers (BTM) and blood bone biochemistry at enrolment, 6, 12, and 36 months. Results: No statistically significant differences were found between the three groups for DXA outcome parameters, i.e., BMDa (L2–L4 BMDa g/cm 2 ), bone mineral apparent density (L2–L4 BMAD g/cm 3 ) and total body less head BMDa (TBLH g/cm 2 ). All blood biochemistry markers were within the reference ranges, and BTM showed active bone turnover with a trend for BTM to decrease with increasing age. Conclusions: Bone density was clinically normal, although the median z scores were below the population mean. BTM showed active bone turnover and blood biochemistry was within the reference ranges. There appeared to be no advantage to bone density, mass, or geometry from taking a macropeptide-based protein substitute as compared with L-AAs.

Item Type: Article
Uncontrolled Keywords: amino acid protein substitute,blood biochemistry,bone mineral density,bone turnover markers,casein glycomacropeptide,osteoporosis,pku,food science,nutrition and dietetics ,/dk/atira/pure/subjectarea/asjc/1100/1106
Faculty \ School: Faculty of Medicine and Health Sciences > Norwich Medical School
Related URLs:
Depositing User: LivePure Connector
Date Deposited: 22 Jul 2021 00:06
Last Modified: 24 Jul 2021 00:08
URI: https://ueaeprints.uea.ac.uk/id/eprint/80680
DOI: 10.3390/nu13062075

Actions (login required)

View Item View Item