Physiologic regulators of bone turnover in adolescents with anorexia nervosa

s of Research Presentations Presented at the Annual Meeting of The Society for Adolescent Medicine—March 2002 SESSION I NEW INVESTIGATOR AWARD ELIGIBLE SCIENTIFIC RESEARCH PAPERS PHYSIOLOGIC REGULATORS OF BONE TURNOVER IN ADOLESCENTS WITH ANOREXIA NERVOSA Catherine M. Gordon, M.D., M.Sc., Elizabeth Goodman, M.D., S. Jean Emans, M.D., Estherann Grace, M.D., Kelly A. Becker, B.A., Clifford J. Rosen, M.D., Caren M. Gundberg, Ph.D., Meryl S. LeBoff, M.D. Division of Adolescent and Young Adult Medicine, and Division of Endocrinology, Children’s Hospital, Boston; Division of Adolescent Medicine, Children’s Hospital of Cincinnati, Cincinnati, OH; St. Joseph Hospital, Bangor, ME; Department of Orthopedics, Yale-New Haven Hospital, New Haven, CT; Division of Endocrine/Hypertension, Brigham and Women’s Hospital, Boston, MA. Purpose: Profound osteopenia is a frequent and often irreversible complication of anorexia nervosa (AN), but controversy exists around the mechanisms responsible for the bone loss of this disease. The goal of this study was to clarify the role of specific physiologic regulators of bone turnover in adolescents with AN. We sought to determine correlates of bone mineral density (BMD), with a focus on the contributions of exercise, specific indices of body mass, and adrenal androgens. Methods: Sixty-one young women with AN were studied. Anthropometric data were acquired, and BMD and body composition measured by dual energy x-ray absorptiometry (DXA). Serum samples were obtained for adrenal and sex steroids, insulin-like growth factor I (IGF-I), proresorptive cytokines, and bone formation markers (osteocalcin and bone-specific alkaline phosphatase), and urine for bone resorption markers (N-telopeptides, NTx). Results: Forty-seven percent of patients with AN had osteopenia of the lumbar spine, and BMD was positively correlated with weight (r .46, p .001), height (r .33, p .008), and weekly exercise (r .36, p .006), and inversely correlated with duration of AN (r .26, p .041). BMD of the hip was positively correlated with weight (r .39, p .002) and exercise (r .42, p .001), and negatively correlated with duration of amenorrhea (r .27, p .044). Levels of dehydroepiandrosterone sulfate (DHEAS), IGF-I, and bone formation markers were below that expected for age, while NTx levels were elevated. DHEAS levels were inversely correlated with NTx (r .40, p .004). IGF-I was directly correlated with BMI (r .32, p .014), percentage body fat (r .31, p .034), and the bone formation marker, osteocalcin (r .32, p .015). Proresorptive cytokine levels were low or undetectable. Conclusions: These results suggest that exercise, height, and weight are positive predictors of BMD in AN, and duration of disease and amenorrhea are negative predictors. If cautiously prescribed, exercise may be a lifestyle factor that could augment bone density in adolescent girls with AN. DHEAS was inversely correlated with bone resorption markers, suggesting a relationship between this adrenal steroid and increased bone resorption in AN. IGF-I was correlated with body mass and bone formation indices. The unexpected finding of low proresorptive cytokines suggests that other mechanisms contribute to the increased bone resorption seen in AN. A NEW PROBLEM IN PEDIATRIC AND ADOLESCENT MEDICINE: THE PSYCHIATRIC BOARDER Jonathan M. Mansbach, M.D., Elizabeth Wharff, Ph.D., S. Bryn Austin, Sc.D., Katherine Ginnis, M.S.W., Elizabeth R. Woods, M.D., M.P.H. Children’s Hospital Boston, Harvard Medical School, Boston, MA. Purpose: Due to the shortage of pediatric and adolescent mental health services, pediatric patients requiring psychiatric hospitalization may be admitted to a medical service only because there are no available inpatient psychiatric beds. These patients are termed psychiatric ‘boarders.‘ The goals of this study were to describe the extent of the boarder crisis and to compare the characteristics of patients successfully placed into psychiatric facilities from the Emergency Department (ED) to those requiring admission to the medical service as a boarder. A psychiatric facility was considered an inpatient psychiatric unit or acute residential treatment center. Methods: We conducted a retrospective cohort study. The cohort consisted of all patients presenting to a large pediatric ED who required inpatient psychiatric admission between July 1, 1999 and June 30, 2000. Extensive data were collected at the time of ED evaluation by psychiatrists, psychologists, and psychiatric social workers. Patients were excluded if they needed inpatient medical stabilization or treatment prior to psychiatric placement. The outcomes were validated using computerized medical records and an inpatient psychiatric consult log. Multivariate logistic regression was used to estimate the odds of being boarded associated JOURNAL OF ADOLESCENT HEALTH 2002;30:92–105 © Society for Adolescent Medicine, 2002 Published by Elsevier Science Inc., 655 Avenue of the Americas, New York, NY 1001