Journal of Adolescent Health 60 (2017) 229e232
www.jahonline.org Adolescent health brief
Effect of Exercise and Antidepressants on Skeletal Outcomes in Adolescent Girls With Anorexia Nervosa Amy D. DiVasta, M.D., M.M.Sc. a, b, *, Henry A. Feldman, Ph.D. c, d, Jennifer M. O’Donnell e, Jin Long, Ph.D. f, Mary B. Leonard, M.D. f, and Catherine M. Gordon, M.D., M.Sc. g a
Division of Adolescent Medicine, Boston Children’s Hospital and Harvard Medical School, Boston, Massachusetts Division of Gynecology, Boston Children’s Hospital and Harvard Medical School, Boston, Massachusetts c Clinical Research Program, Boston Children’s Hospital, Boston, Massachusetts d Division of Endocrinology, Boston Children’s Hospital, Boston, Massachusetts e Rutgers-Robert Wood Johnson Medical School, New Brunswick, New Jersey f Division of Pediatric Nephrology, Stanford University School of Medicine, Palo Alto, California g Division of Adolescent and Transition Medicine, Cincinnati Children’s Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, Ohio b
Article history: Received July 21, 2016; Accepted October 7, 2016 Keywords: Anorexia nervosa; Malnutrition; Peripheral quantitative computed tomography; DXA; Exercise; Antidepressant
A B S T R A C T
Purpose: We examined the relationships between malnutrition, lifestyle factors, and bone health in anorexia nervosa (AN) via dual-energy X-ray absorptiometry (DXA) and peripheral quantitative computed tomography (pQCT). Methods: Seventy adolescent girls with AN and 132 normal-weighted controls underwent pQCT tibial measures including trabecular volumetric bone mineral density (vBMD), cortical vBMD, and cortical thickness. Participants with AN underwent DXA measures of the axial skeleton. We assessed the association of DXA and pQCT measures with clinical and lifestyle variables. Results: Body mass index Z-score and ideal body weight percentage were positively correlated with trabecular vBMD, cortical CSA, and section modulus (p < .04). Exercise was associated with all pQCT measures but only with hip BMD by DXA. In AN, the use of antidepressants was associated with lower pQCT measures (p < .03). Conclusions: Antidepressants may negatively, and exercise positively, influence BMD in adolescents with eating disorders. These findings offer a provocative look at two longstanding questions. Ó 2016 Society for Adolescent Health and Medicine. All rights reserved.
Bone loss frequently complicates anorexia nervosa (AN) [1,2]; patients have a seven-fold increased fracture incidence [3]. Studies using dual-energy X-ray absorptiometry (DXA) demonstrate significant reductions in bone mineral density (BMD) [1]. Several factors correlate with BMD in AN: body mass index (BMI), Conflicts of Interest: The authors have no conflicts of interest to disclose. * Address correspondence to: Amy D. DiVasta, M.D., M.M.Sc., Division of Adolescent Medicine, Boston Children’s Hospital, 333 Longwood Avenue, Boston, MA 02115. E-mail address:
[email protected] (A.D. DiVasta). 1054-139X/Ó 2016 Society for Adolescent Health and Medicine. All rights reserved. http://dx.doi.org/10.1016/j.jadohealth.2016.10.003
IMPLICATIONS AND CONTRIBUTION
The impact of malnutrition and accompanying systemic alterations on the peripheral skeleton of adolescents with anorexia nervosa may be similar to that of the axial skeleton. While exercise positively influences bone mineral density even in the setting of anorexia nervosa, antidepressant use appears to negatively impact the skeleton.
age at menarche, lean body mass, and illness duration [1]. Less is known about the impact of modifiable factors, such as physical activity or medication use, on the peripheral skeleton or bone geometry of girls with AN. We sought to determine the association between these factors and skeletal health as measured by DXA and peripheral quantitative computed tomography (pQCT). We hypothesized that physical activity would be protective for skeletal health even in the setting of AN, whereas the use of antidepressant medications would not significantly impact bone measurements in these patients.
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A.D. DiVasta et al. / Journal of Adolescent Health 60 (2017) 229e232
Table 1 Characteristics of 70 adolescent girls with anorexia nervosa and 132 female control subjects of comparable age Characteristic
ANa
Control
Mean SD Age, years Height, cm Weight, kg BMI, kg/m2 BMI Z-score % IBW Lean mass, kg Fat mass, kg Body fat, %
15.5 160.5 48.4 18.7 .60 91.0 34.5 11.9 24.4
1.9 7.9 6.5 1.7 .79 9.4 4.9 3.3 5.2
Mean SD
11.5, 18.9 142.0, 178.0 25.9, 59.4 12.8, 22.4 3.13, .82 56.9, 111.0 18.9, 50.0 3.6, 18.6 11.0, 33.5
16.9 161.9 59.4 22.6 .41 109.6
Duration of AN, months Duration of amenorrhea, monthsa
Race White Black Asian Other Native American Hispanic ethnicity Regular exercise Antidepressant use Vitamin D insufficient (25OHD
