Faculty Bibliography

Providing medical care and managing the health care needs of adolescents can be a complex process. Knowing, which adolescents can consent to health care and the scope of services adolescents can consent to, what information can be kept confidential and from whom, under which circumstances information must be disclosed, and how to navigate parental involvement, is vital for the practice of adolescent medicine. This chapter aims to address some of these issues and assist health care providers in gaining knowledge and expertise in the optimal delivery of care for adolescents.

OBJECTIVE: To examine the relationship between bone mass and serum levels of 25-hydroxyvitamin D and parathyroid hormone in African-American adolescent girls. STUDY DESIGN: A cross-sectional sample at a suburban research center. METHODS: Twenty-one adolescent black girls 12-14 years of age, were studied during winter with biochemical measurements of serum 25-hydroxyvitamin D (25-OHD) and parathyroid hormone (PTH). Bone mass assessment was done with dual energy x-ray absorbsiometry (DXA) and peripheral quantitative computed tomography of the radius (p-QCT). Anthropometric, physical activity and nutritional data were collected. RESULTS: All participants were vitamin-D deficient (serum 25-OHD level <50 nmol/L), of whom nine (43%) were severely vitamin-D deficient (serum 25-OHD level <20 nmol/L). Mean daily intake of dietary calcium was 540 mg/d and vitamin D was 195 IU/d. There was a positive correlation, although statistically not significant, between serum 25-OHD and various bone mass measurements. Serum PTH was inversely correlated to total body BMD (r = -0.51, p = 0.02) and other bone mineral density at the lumbar spine, total femur and mid-radius. CONCLUSION: Vitamin-D insufficiency is a widely prevalent problem among adolescent African-American girls. Our data implies that enhancing vitamin-D nutrition resulting in lower serum PTH levels could potentially influence their peak bone mass.