Carmelo Messina1, Ciriaco Buonomenna2, Giorgia Menon3, Sandro Magnani2, Domenico Albano3, Salvatore Gitto2, Fabio Massimo Ulivieri4, Luca Maria Sconfienza5. 1. Unità Operativa di Radiologia Diagnostica ed Interventistica, IRCCS Istituto Ortopedico Galeazzi, Milan, Italy; Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Milan, Italy. Electronic address: carmelo.messina@unimi.it. 2. Scuola di Specializzazione in Radiodiagnostica, Università degli Studi di Milano, Milan, Italy. 3. Unità Operativa di Radiologia Diagnostica ed Interventistica, IRCCS Istituto Ortopedico Galeazzi, Milan, Italy. 4. Bone Metabolic Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Medicina Nucleare, Milan, Italy. 5. Unità Operativa di Radiologia Diagnostica ed Interventistica, IRCCS Istituto Ortopedico Galeazzi, Milan, Italy; Dipartimento di Scienze Biomediche per la Salute, Università degli Studi di Milano, Milan, Italy.
Abstract
INTRODUCTION: Trabecular bone score (TBS) is an indirect index of trabecular microarchitecture derived from lumbar spine dual-energy X-ray absorptiometry. Previous phantom study showed that an increase in soft tissue thickness does not affect TBS reproducibility. We investigated the effect of increasing body mass index (BMI) and waist circumference on TBS precision error on patients, compared to bone mineral density (BMD). METHODOLOGY: A population of postmenopausal Caucasian women was distributed in 3 different BMI (normal, overweight, and class I obesity), plus 2 further groups based on waist circumference diameter (≤88 cm and >88 cm, respectively). In vivo precision error was calculated on 30 consecutive subjects that were scanned 2 times, with patient repositioning, using the Hologic QDR-Discovery W densitometer. Coefficient of variation, percent least significant change, and reproducibility were calculated according to the International Society for Clinical Densitometry guidelines. RESULTS: Ninety-five women aged 66 ± 10 (mean ± standard deviation) were included. No significant differences were found both for BMD and TBS precision errors, respectively, when comparing BMI groups and waist circumference groups. BMD reproducibility ranged from 95.9% (BMI > 30 kg/m2) to 97.5% (BMI < 25 kg/m2). TBS reproducibility ranged between 95.8% (BMI = 25-29.9 kg/m2, waist circumference > 88 cm) and 96.6% (BMI < 25 kg/m2). With the exception of obese group, a significant difference was found between BMD and TBS reproducibility, being that of TBS slightly lower than BMD. A significant decrease of TBS values was found between normal and obese subjects, as well as between waist circumference groups. CONCLUSIONS: TBS precision error is not affected by BMI and waist circumference differences. TBS reproducibility showed to be slightly lower than that of BMD, but this difference was mitigated in obese patients. A negative association was found between the amount of fat mass and TBS mean values.
INTRODUCTION: Trabecular bone score (TBS) is an indirect index of trabecular microarchitecture derived from lumbar spine dual-energy X-ray absorptiometry. Previous phantom study showed that an increase in soft tissue thickness does not affect TBS reproducibility. We investigated the effect of increasing body mass index (BMI) and waist circumference on TBS precision error on patients, compared to bone mineral density (BMD). METHODOLOGY: A population of postmenopausal Caucasian women was distributed in 3 different BMI (normal, overweight, and class I obesity), plus 2 further groups based on waist circumference diameter (≤88 cm and >88 cm, respectively). In vivo precision error was calculated on 30 consecutive subjects that were scanned 2 times, with patient repositioning, using the Hologic QDR-Discovery W densitometer. Coefficient of variation, percent least significant change, and reproducibility were calculated according to the International Society for Clinical Densitometry guidelines. RESULTS: Ninety-five women aged 66 ± 10 (mean ± standard deviation) were included. No significant differences were found both for BMD and TBS precision errors, respectively, when comparing BMI groups and waist circumference groups. BMD reproducibility ranged from 95.9% (BMI > 30 kg/m2) to 97.5% (BMI < 25 kg/m2). TBS reproducibility ranged between 95.8% (BMI = 25-29.9 kg/m2, waist circumference > 88 cm) and 96.6% (BMI < 25 kg/m2). With the exception of obese group, a significant difference was found between BMD and TBS reproducibility, being that of TBS slightly lower than BMD. A significant decrease of TBS values was found between normal and obese subjects, as well as between waist circumference groups. CONCLUSIONS:TBS precision error is not affected by BMI and waist circumference differences. TBS reproducibility showed to be slightly lower than that of BMD, but this difference was mitigated in obesepatients. A negative association was found between the amount of fat mass and TBS mean values.
Authors: Heidi J Kalkwarf; John A Shepherd; Didier Hans; Elena Gonzalez Rodriguez; Joseph M Kindler; Joan M Lappe; Sharon Oberfield; Karen K Winer; Babette S Zemel Journal: J Bone Miner Res Date: 2022-02-23 Impact factor: 6.390