title: Inclusion of Regional Body Composition Parameters Improves Bone Mineral Density Cross-Calibration Between GE Lunar Prodigy and iDXA Densitometers.
abstract: Since 1989, the Kuopio Osteoporosis Risk Factor and Prevention (OSTPRE, n = 14220) Study has followed long-term changes of bone mineral density (BMD) and body composition in women with GE Lunar devices. During the course of OSTPRE, the dual-energy X-ray absorptiometry device had to be replaced by a newer model. Then, it was essential to determine whether systematic measurement differences in BMD and body composition will occur. As a part of the OSTPRE study, BMD was measured in 54 women, whereas body composition was determined in 55 women, aged 27-71, by using both the GE Healthcare Lunar Prodigy and iDXA narrow-angle fan beam densitometers during the same visit. The total body fat mass (FM) and lean body mass (LBM) results of these scanners showed a high linear correlation (r = 0.981-0.994, p < 0.0001). However, the mean total body FM and LBM values measured by iDXA were on average 2.3% (0.5 kg, 95% confidence interval: 0.3-0.7 kg) higher and 0.8% (0.3 kg, 95% confidence interval: 0.1-0.6 kg) lower, respectively, than those measured by Prodigy. Inclusion of local soft tissue measurements (total body LBM, legs/android FM) improved the agreement of total body, total hip, and lumbar spine BMD values between the devices but not femoral neck BMD agreement. Equations, based on linear regression analyses, were derived to minimize differences between the instruments. Then, the differences in BMD and body composition measurements were negligible between Prodigy and iDXA. Using correction equations enables an objective comparison of longitudinal BMD and body composition measurements.
authors.affiliation: Kuopio Musculoskeletal Research Unit (KMRU), Surgery, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland. Electronic address: jtsaarel@student.uef.fi.
authors.forename: J
authors.initials: J
authors.lastname: Saarelainen
authors.affiliation: Department of Applied Physics, University of Eastern Finland, Kuopio, Finland; Department of Clinical Physiology and Nuclear Medicine, Kuopio University Hospital, Kuopio, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Hakulinen
authors.affiliation: Kuopio Musculoskeletal Research Unit (KMRU), Surgery, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland.
authors.forename: T
authors.initials: T
authors.lastname: Rikkonen
authors.affiliation: Kuopio Musculoskeletal Research Unit (KMRU), Surgery, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland; Department of Orthopaedics, Traumatology and Hand Surgery, Kuopio University Hospital, Kuopio, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Kröger
authors.affiliation: Institute of Clinical Medicine, Psychiatry, University of Eastern Finland, Kuopio, Finland; Departments of Psychiatry, Kuopio University Hospital, Kuopio, Finland; Department of Psychiatry, South-Savonia Hospital District, Mikkeli, Finland; Department of Psychiatry, North Karelia Central Hospital, Joensuu, Finland; Department of Psychiatry, SOSTERI, Savonlinna, Finland; Department of Psychiatry, SOTE, Iisalmi, Finland; Department of Psychiatry, Lapland Hospital District, Rovaniemi, Finland; Clinic of Child Psychiatry, University Hospital of Oulu, Oulu, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Koivumaa-Honkanen
authors.affiliation: Kuopio Musculoskeletal Research Unit (KMRU), Surgery, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland.
authors.forename: R
authors.initials: R
authors.lastname: Honkanen
authors.affiliation: Department of Applied Physics, University of Eastern Finland, Kuopio, Finland; Diagnostic Imaging Centre, Kuopio University Hospital, Kuopio, Finland.
authors.forename: J S
authors.initials: JS
authors.lastname: Jurvelin
mesh_terms: D015502:Absorptiometry, Photon / Q000295:instrumentation*; D000328:Adult; D000368:Aged; D001823:Body Composition; D015519:Bone Density; D001842:Bone and Bones / Q000000981:diagnostic imaging; D002138:Calibration; D005260:Female; D005272:Femur Neck / Q000000981:diagnostic imaging*; D006801:Humans; D016014:Linear Models; D008159:Lumbar Vertebrae / Q000000981:diagnostic imaging*; D008875:Middle Aged
keywords: Body composition; bone mineral density; cross-calibration