Format

Send to

Choose Destination
J Clin Endocrinol Metab. 2015 Mar;100(3):1018-27. doi: 10.1210/jc.2014-3096. Epub 2014 Dec 11.

The choice of normative pediatric reference database changes spine bone mineral density Z-scores but not the relationship between bone mineral density and prevalent vertebral fractures.

Author information

1
Children's Hospital of Eastern Ontario Research Institute (J.M., M.S.), Ottawa, ON; University of Alberta (K.S., R.C.), Edmonton, AB; Université de Montréal (N.A.), Montréal, QC; University of Ottawa (J.H., M.M., N.S., L.M.W.), Ottawa, ON; University of Calgary (J.H.), Calgary, AB; University of British Columbia (B.L., D.A.C.), Vancouver, BC; McMaster University (S.A., R.B.), Hamilton, ON; Dalhousie University (E.A.C., C.V.F.), Halifax, NS; University of Toronto (R.M.G.), Toronto, ON; University of Manitoba (C.R.), Winnipeg, MB; McGill University (A.M.S., F.R.), Montréal, QC.

Abstract

OBJECTIVES:

Our objectives were to assess the magnitude of the disparity in lumbar spine bone mineral density (LSBMD) Z-scores generated by different reference databases and to evaluate whether the relationship between LSBMD Z-scores and vertebral fractures (VF) varies by choice of database.

PATIENTS AND DESIGN:

Children with leukemia underwent LSBMD by cross-calibrated dual-energy x-ray absorptiometry, with Z-scores generated according to Hologic and Lunar databases. VF were assessed by the Genant method on spine radiographs. Logistic regression was used to assess the association between fractures and LSBMD Z-scores. Net reclassification improvement and area under the receiver operating characteristic curve were calculated to assess the predictive accuracy of LSBMD Z-scores for VF.

RESULTS:

For the 186 children from 0 to 18 years of age, 6 different age ranges were studied. The Z-scores generated for the 0 to 18 group were highly correlated (r ≥ 0.90), but the proportion of children with LSBMD Z-scores ≤-2.0 among those with VF varied substantially (from 38-66%). Odds ratios (OR) for the association between LSBMD Z-score and VF were similar regardless of database (OR = 1.92, 95% confidence interval 1.44, 2.56 to OR = 2.70, 95% confidence interval 1.70, 4.28). Area under the receiver operating characteristic curve and net reclassification improvement ranged from 0.71 to 0.75 and -0.15 to 0.07, respectively.

CONCLUSIONS:

Although the use of a LSBMD Z-score threshold as part of the definition of osteoporosis in a child with VF does not appear valid, the study of relationships between BMD and VF is valid regardless of the BMD database that is used.

PMID:
25494661
PMCID:
PMC4519277
DOI:
10.1210/jc.2014-3096
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Silverchair Information Systems Icon for PubMed Central
Loading ...
Support Center