Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2016 Nov 2;11(11):e0165727.
doi: 10.1371/journal.pone.0165727. eCollection 2016.

The Clinical and Biochemical Predictors of Bone Mass in Preterm Infants

Justyna Czech-Kowalska  1 , Edyta Czekuc-Kryskiewicz  2 , Pawel Pludowski  2 , Katarzyna Zaniuk  3 , Maciej Jaworski  2 , Anna Łuba  1 , Karolina Grzybowska  1 , Krystyna Piłat  1 , Anna Dobrzanska  1
Affiliations

The Clinical and Biochemical Predictors of Bone Mass in Preterm Infants

Justyna Czech-Kowalska et al. PLoS One. .

Abstract

Background: Metabolic bone disease of prematurity still occurs in preterm infants, although a significant improvement in neonatal care has been observed in recent decades. Dual-energy X-ray absorptiometry (DXA) is the precise technique for assessing bone mineral content (BMC) in preterm infants, but is not widely available.

Aim: To investigate the clinical and biochemical parameters, including bone metabolism markers as potential predictors of BMC, in preterm infants up to 3 months corrected age (CA).

Materials and methods: Ca-P homeostasis, iPTH, 25-hydroxyvitamin D, osteocalcin, N-terminal propeptide, cross-linked C-telopeptide and amino-terminal pro C-type natriuretic peptide and the DXA scans were prospectively performed in 184 preterm infants (≤ 34 weeks' gestation) between term age and 3 mo CA. Lower bone mass was defined as BMC below or equal to respective median value for the whole study group, rounded to the nearest whole number.

Results: The appropriate quality DXA scans were available for 160 infants (87%) examined at term and for 130 (71%) tested at 3 mo CA. Higher iPTH level was the only independent predictor of lower BMC at term, whereas lower BMC at 3 mo CA was associated both with lower urinary phosphate excretion and higher serum osteocalcin level. ROC analysis showed that iPTH >43.6 pg/mL provided 40% sensitivity and 88% specificity in identification of preterm infants with lower BMC at term. In turn, urinary phosphate excretion (TRP>97% or UP/Cr ≤0.74 mg/mg) and serum osteocalcin >172 ng/mL provided 40% sensitivity and 93% specificity in identification of infants with decreased BMC at 3 mo CA.

Conclusion: Serum iPTH might to be a simple predictor of reduced BMC in preterm infants at term age, but urinary phosphate excretion and serum osteocalcin might predict reduced BMC at 3 mo CA. These results represent a promising diagnostic tool based on simple, widely available biochemical measurements for bone mass assessment in preterm infants.

PubMed Disclaimer

Conflict of interest statement

The authors have declared that no competing interests exist.

Figures

Fig 1
Fig 1. ROC curves for predicting reduced BMC in preterm infants at 3 mo CA.
UP/Cr ratio–urinary phosphate to creatinine ratio in the spot urine sample, TRP–tubular reabsorption of phosphate, OC–serum osteocalcin.
See this image and copyright information in PMC

References

    1. Backström MC, Mäki R, Kuusela AL, Sievänen H, Koivisto AM, Ikonen RS, et al. Randomised controlled trial of vitamin D supplementation on bone density and biochemical indices in preterm infants. Arch Dis Child Fetal Neonatal Ed. 1999;80(3):F161–6. - PMC - PubMed
    1. Pieltain C, de Halleux V, Senterre T, Rigo J. Prematurity and bone health. World Rev Nutr Diet. 2013;106:181–8. 10.1159/000342680 - DOI - PubMed
    1. Christmann V, de Grauw AM, Visser R, Matthijsse RP, van Goudoever JB, van Heijst AF. Early postnatal calcium and phosphorus metabolism in preterm infants. J Pediatr Gastroenterol Nutr. 2014;58(4):398–403. 10.1097/MPG.0000000000000251 - DOI - PubMed
    1. Viswanathan S, Khasawneh W, McNelis K, Dykstra C, Amstadt R, Super DM, et al. Metabolic bone disease: a continued challenge in extremely low birth weight infants. JPEN J Parenter Enteral Nutr. 2014;38(8):982–90. 10.1177/0148607113499590 - DOI - PubMed
    1. Visser F, Sprij AJ, Brus F. The validity of biochemical markers in metabolic bone disease in preterm infants: a systematic review. Acta Paediatr. 2012;101(6):562–8. 10.1111/j.651-2227.012.02626.x Epub 2012 Mar 6. - DOI - PubMed