Body Composition Assessment in Adult Females with Anorexia Nervosa and Bulimia Nervosa-A Cross-Sectional Study Comparing Dual-Energy X-Ray Absorptiometry Scan and Isotopic Dilution of Deuterium

Mariana P Lopes; Karina Pfrimer; Eduardo Ferriolli; Marle S Alvarenga; Ligia A Martini

doi:10.1016/j.tjnut.2023.03.019

Body Composition Assessment in Adult Females with Anorexia Nervosa and Bulimia Nervosa-A Cross-Sectional Study Comparing Dual-Energy X-Ray Absorptiometry Scan and Isotopic Dilution of Deuterium

J Nutr. 2023 May;153(5):1309-1322. doi: 10.1016/j.tjnut.2023.03.019. Epub 2023 Mar 18.

Authors

Mariana P Lopes¹, Karina Pfrimer², Eduardo Ferriolli², Marle S Alvarenga³, Ligia A Martini⁴

Affiliations

¹ Nutrition Department, School of Public Health, University of São Paulo, Brazil; Section of Eating Disorders, Department of Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College, London, United Kingdom. Electronic address: mariana.lopes@kcl.ac.uk.
² Department of Nutrition, Ribeirão Preto Medical School, University of São Paulo, Brazil.
³ Post-graduation Program in Nutrition in Public Health, School of Public Health, University of São Paulo, Brazil.
⁴ Nutrition Department, School of Public Health, University of São Paulo, Brazil.

PMID: 36934952
DOI: 10.1016/j.tjnut.2023.03.019

Abstract

Background: Eating disorders (EDs) compromise individuals' nutritional status, affecting, among other organs and systems, bone health.

Objectives: This study aimed to assess and compare bone mineral density (BMD) from DXA scan and deuterium (D₂O) dilution of adult females with anorexia nervosa (AN) and bulimia nervosa (BN).

Methods: This was a cross-sectional study with 53 female participants (18-49 y) with a diagnosis of AN (n = 25) or BN (n = 28). DXA scan was performed to assess BMD, FM, and FFM, and D₂O dilution was used to assess total body water (TBW), FM, and FFM. Interviews/questionnaires were used to assess symptoms, illness trajectory, and physical activity. t-test, chi-square test, Pearson's linear correlation, linear regressions, and Bland-Altman analyses were performed, with a significance level of 5%.

Results: TBW below the recommended level for adult females (≥ 45%) was more frequent in BN (60%) compared with AN (21%; P = 0.013). FM index (FMI) (soft tissue only) (t-test P = 0.06), and FFM index (FFMI) (t-test P = 0.08) agreed between DXA scan and D₂O dilution. Only FFMI did not show systematic bias of proportion (β: -0.2, P = 0.177). The diagnosis of BN, binge-eating episodes, and physical activity in AN were associated with the differences in the methods' results. FMI was positively associated with BMD in AN, and both FMI and FFMI were positively associated with BMD in BN.

Conclusions: In adult females with EDs, DXA scan and D₂O dilution achieved agreement for FMI and FFMI. Changes in FM and FFM are important in understanding the mechanisms behind bone loss in EDs. Protocols for body composition assessment in EDs can help to minimize the effect of the ED diagnosis, ED behaviors (that is, excessive exercise and purging behaviors), and weight on the accuracy of measurements.

Keywords: bone mineral density; eating disorders; fat mass; fat-free mass; total body water.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Absorptiometry, Photon / methods
Adult
Anorexia Nervosa*
Body Composition
Bulimia Nervosa*
Cross-Sectional Studies
Deuterium
Female
Humans

Substances

Deuterium