Is Discordance in Bone Measurements Affected by Body Composition or Anthropometry? A Comparative Study Between Peripheral and Central Devices

Saarelainen, J.; Rikkonen, T.; Honkanen, R.; Kröger, H.; Tuppurainen, M.; Niskanen, L.; Jurvelin, J.S.

doi:10.1016/j.jocd.2007.03.003

« Previous Next »Journal of Clinical Densitometry
Volume 10, Issue 3 , Pages 312-318, July 2007

Is Discordance in Bone Measurements Affected by Body Composition or Anthropometry? A Comparative Study Between Peripheral and Central Devices

J. Saarelainen
- Bone and Cartilage Research Unit, Clinical Research Center, University of Kuopio, Kuopio, Finland
- Address correspondence to: Jarmo Saarelainen, Med. Stud., Bone and Cartilage Research Unit, Clinical Research Center, University of Kuopio, POB 1627, 70211 Kuopio, Finland.
T. Rikkonen
- Bone and Cartilage Research Unit, Clinical Research Center, University of Kuopio, Kuopio, Finland
R. Honkanen
- Bone and Cartilage Research Unit, Clinical Research Center, University of Kuopio, Kuopio, Finland
- Research Institute of Public Health, University of Kuopio, Kuopio, Finland
H. Kröger
- Bone and Cartilage Research Unit, Clinical Research Center, University of Kuopio, Kuopio, Finland
- Department of Surgery/Orthopaedics and Traumatology, Kuopio University Hospital, Kuopio, Finland
M. Tuppurainen
- Bone and Cartilage Research Unit, Clinical Research Center, University of Kuopio, Kuopio, Finland
- Department of Obstetrics and Gynaecology, Kuopio University Hospital, Kuopio, Finland
L. Niskanen
- Department of Medicine, Kuopio University Hospital, Kuopio, Finland
J.S. Jurvelin
- Department of Physics, University of Kuopio, Kuopio, Finland
- Department of Clinical Physiology and Nuclear Medicine, Kuopio University Hospital, Kuopio, Finland

Received 13 September 2006; received in revised form 9 March 2007; accepted 13 March 2007. published online 25 April 2007.

Abstract

Screening of osteoporosis using peripheral bone measurements has become more common, even though diagnostic discrepancies are known to exist between peripheral dual-energy X-ray (pDXA) or quantitative ultrasound (QUS) and central DXA measurements. Values of diagnostic parameters such as bone mineral density, speed of (ultra)sound, and broadband ultrasound attenuation are affected by bone size and soft tissue composition. However, their significance for the discordance between peripheral and central techniques is unclear. In this study, bone status and total body composition of 139 women (mean age 68.3yr [1.7 SD], mean body mass index 26.5kg/m² [3.6 SD]) were assessed by 3 GE Lunar devices. Heel pDXA and heel QUS were conducted using peripheral instantaneous X-ray imaging (PIXI) and Achilles, respectively, and central DXA measurements were taken at the posterior-anterior lumbar spine (L2–L4) and at the left femoral neck using Prodigy. Positive significant associations were found between body height or fat (%) and most DXA or QUS parameters. The discordance between the site-dependent DXA or QUS T-score values typically increased (p<0.05) as a function of body weight or fat (%), but not with body height. On an average, body adiposity accounted for less than 11% of the differences between the techniques; however, increase of total body fat from 20% to 45% led to a discrepancy of one T-score between DXA_HEEL and QUS_HEEL. To avoid diagnostic bias, comparative assessment of the devices using the same population is recommended.