TY - JOUR
T1 - Tracking of bone mass and density during childhood and adolescence
AU - Kalkwarf, Heidi J.
AU - Gilsanz, Vicente
AU - Lappe, Joan M.
AU - Oberfield, Sharon
AU - Shepherd, John A.
AU - Hangartner, Thomas N.
AU - Huang, Xangke
AU - Frederick, Margaret M.
AU - Winer, Karen K.
AU - Zemel, Babette S.
N1 - Funding Information:
This work was supported by the National Institute of Child Health and Human Development contracts NO1-HD-1-3228, −3329, −3330, −3331, −3332, and − 3333 and the National Center for Research Resources Grants M01-RR-08084 and −000240 .
Funding Information:
Disclosure Summary: J.A.S. has received a research grant from Hologic, Inc. H.J.K., V.G., J.M.L., S.O., T.N.H., X.H., M.M.F., K.K.W., and B.S.Z. have nothing to disclose.
PY - 2010/4
Y1 - 2010/4
N2 - Context: Whether a child with low bone mineral density (BMD) at one point in time will continue to have low BMD, despite continued growth and maturation, is important clinically. The stability of a characteristic during growth is referred to as "tracking." Objective: We examined the degree of tracking in bone mineral content (BMC) and BMD during childhood and adolescence and investigated whether tracking varied according to age, sexual maturation, and changes in growth status. Design: We conducted a longitudinal study with measurements at baseline and annually for 3 yr. Setting: The Bone Mineral Density in Childhood Study was conducted at five clinical centers in the United States. Study Participants: A total of 1554 girls and boys, ages 6-16 yr at baseline, participated in the study. Main Outcome Measures: Whole body, spine, hip, and forearm BMC and BMD were measured by dual-energy x-ray absorptiometry, and age-, sex-, and race-specific Z-scores were calculated. Deviation from tracking was calculated as the Z-score at yr 3 minus baseline. Results: Correlations between Z-scores at baseline and yr 3 ranged from 0.76-0.88. Among children with a Z-score below -1.5 at baseline, 72-87% still had a Z-score below -1 after 3 yr. Age, sexual maturation, and deviations in growth status (P <0.01) were associated with deviation from tracking; however, tracking was strongly evident even after adjusting for the effects of age, maturation, and growth. Conclusions: Bone density showed a high degree of tracking over 3 yr in children and adolescents. Healthy children with low bone density will likely continue to have low bone density unless effective interventions are instituted.
AB - Context: Whether a child with low bone mineral density (BMD) at one point in time will continue to have low BMD, despite continued growth and maturation, is important clinically. The stability of a characteristic during growth is referred to as "tracking." Objective: We examined the degree of tracking in bone mineral content (BMC) and BMD during childhood and adolescence and investigated whether tracking varied according to age, sexual maturation, and changes in growth status. Design: We conducted a longitudinal study with measurements at baseline and annually for 3 yr. Setting: The Bone Mineral Density in Childhood Study was conducted at five clinical centers in the United States. Study Participants: A total of 1554 girls and boys, ages 6-16 yr at baseline, participated in the study. Main Outcome Measures: Whole body, spine, hip, and forearm BMC and BMD were measured by dual-energy x-ray absorptiometry, and age-, sex-, and race-specific Z-scores were calculated. Deviation from tracking was calculated as the Z-score at yr 3 minus baseline. Results: Correlations between Z-scores at baseline and yr 3 ranged from 0.76-0.88. Among children with a Z-score below -1.5 at baseline, 72-87% still had a Z-score below -1 after 3 yr. Age, sexual maturation, and deviations in growth status (P <0.01) were associated with deviation from tracking; however, tracking was strongly evident even after adjusting for the effects of age, maturation, and growth. Conclusions: Bone density showed a high degree of tracking over 3 yr in children and adolescents. Healthy children with low bone density will likely continue to have low bone density unless effective interventions are instituted.
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U2 - 10.1210/jc.2009-2319
DO - 10.1210/jc.2009-2319
M3 - Article
C2 - 20194709
AN - SCOPUS:77951637240
VL - 95
SP - 1690
EP - 1698
JO - Journal of Clinical Endocrinology and Metabolism
JF - Journal of Clinical Endocrinology and Metabolism
SN - 0021-972X
IS - 4
ER -