Revised reference curves for bone mineral content and areal bone mineral density according to age and sex for black and non-black children: results of the bone mineral density in childhood study

Abstract

Context: Deficits in bone acquisition during growth may increase fracture risk. Assessment of bone health during childhood requires appropriate reference values relative to age, sex, and population ancestry to identify bone deficits.

Objective: The objective of this study was to provide revised and extended reference curves for bone mineral content (BMC) and areal bone mineral density (aBMD) in children.

Design: The Bone Mineral Density in Childhood Study was a multicenter longitudinal study with annual assessments for up to 7 yr.

Setting: The study was conducted at five clinical centers in the United States.

Participants: Two thousand fourteen healthy children (992 males, 22% African-Americans) aged 5-23 yr participated in the study.

Intervention: There were no interventions.

Main outcome measures: Reference percentiles for BMC and aBMD of the total body, lumbar spine, hip, and forearm were obtained using dual-energy x-ray absorptiometry for Black and non-Black children. Adjustment factors for height status were also calculated.

Results: Extended reference curves for BMC and aBMD of the total body, total body less head, lumbar spine, total hip, femoral neck, and forearm for ages 5-20 yr were constructed relative to sex and age for Black and non-Black children. Curves are similar to those previously published for 7-17 year olds. BMC and aBMD values were greater for Black vs. non-Black children at all measurement sites.

Conclusions: We provide here dual-energy x-ray absorptiometry reference data on a well-characterized cohort of 2012 children and adolescents. These reference curves provide the most robust reference values for the assessment and monitoring of bone health in children and adolescents in the literature to date.

Fig. 1.

Reference curves for total hip aBMD for healthy male and female, Black, and non-Black children aged 5–20 yr. Shown are the curves for −2, −1, 0, +1, and +2 sd (Z-scores). Corresponding percentile distributions and L, M, and S values are shown in Supplemental Table 6. The dotted line curves are the previously published BMDCS reference curves (4) for ages 7 to 17 yr based on a subset of observations used to generate the final curves. The error bar to the right of each curve shows the young adult (20–29 yr) reference range (mean ± 2 sd) from the NHANES (12).

Fig. 2.

Reference curves for femoral neck aBMD for healthy male and female, Black, and non-Black children aged 5–20 yr. Shown are the curves for −2, −1, 0, +1, and +2 sd (Z-scores). Corresponding percentile distributions and L, M, and S values are shown in Supplemental Table 8. The dotted line curves are the previously published BMDCS reference curves (4) for ages 7–17 yr based on a subset of observations used to generate the final curves. The error bar to the right of each curve shows the young adult (20–29 yr) reference range (mean ± 2 sd) from the NHANES (12).

Fig. 3.

BMDCS reference curves (solid lines) for TBBMC compared with published values from the NHANES (13) (dashed lines).

Fig. 4.

BMDCS reference curves (solid lines) for TBaBMD compared with published values from the NHANES (13) (dashed lines).