Reference values for bone mineral density in 12-to 18-year-old girls categorized by weight, race, and age

Background: Normative bone mineral density (BMD) values for adults do not apply to the pediatric population because of dramatic and variable rates of bone mineral acquisition that take place throughout adolescence. Objective: This study was designed to provide normative BMD values for the lumbar spine and femoral neck by age, weight, and race in female adolescents for use by clinicians. Materials and methods: The study population comprised 422 healthy adolescent girls aged 12-18 years recruited from four primary-care clinics. BMD measurements were performed with dual-energy X-ray absorptiometry (DEXA). Results: The major statistical predictors of lumbar spine BMD and femoral neck BMD were race, chronological age, and weight. There was an increase in both lumbar spine and femoral neck BMD that paralleled an increase in age and weight. In addition, the lumbar spine BMD and the femoral neck BMD were higher in the black participants than in the non-black participants with mean BMD values in grams per centimeter squared of 1.02 and 0.98, respectively, for blacks and 0.96 and 0.89, respectively, for non-blacks (P<0.001). Conclusion: Our study produced the largest set of lumbar spine and femoral neck BMD normative values for female adolescents and confirms the importance of both demographic and anthropomorphic variables in determining normative BMD values.