title: Visceral Adipose Tissue Is Associated With Bone Microarchitecture in the Framingham Osteoporosis Study.
abstract: Obesity has been traditionally considered to protect the skeleton against osteoporosis and fracture. Recently, body fat, specifically visceral adipose tissue (VAT), has been associated with lower bone mineral density (BMD) and increased risk for some types of fractures. We studied VAT and bone microarchitecture in 710 participants (58% women, age 61.3 ± 7.7 years) from the Framingham Offspring cohort to determine whether cortical and trabecular BMD and microarchitecture differ according to the amount of VAT. VAT was measured from CT imaging of the abdomen. Cortical and trabecular BMD and microarchitecture were measured at the distal tibia and radius using high-resolution peripheral quantitative computed tomography (HR-pQCT). We focused on 10 bone parameters: cortical BMD (Ct.BMD), cortical tissue mineral density (Ct.TMD), cortical porosity (Ct.Po), cortical thickness (Ct.Th), cortical bone area fraction (Ct.A/Tt.A), trabecular density (Tb.BMD), trabecular number (Tb.N), trabecular thickness (Tb.Th), total area (Tt.Ar), and failure load (FL) from micro-finite element analysis. We assessed the association between sex-specific quartiles of VAT and BMD, microarchitecture, and strength in all participants and stratified by sex. All analyses were adjusted for age, sex, and in women, menopausal status, then repeated adjusting for body mass index (BMI) or weight. At the radius and tibia, Ct.Th, Ct.A/Tt.A, Tb.BMD, Tb.N, and FL were positively associated with VAT (all p-trend <0.05), but no other associations were statistically significant except for higher levels of cortical porosity with higher VAT in the radius. Most of these associations were only observed in women, and were no longer significant when adjusting for BMI or weight. Higher amounts of VAT are associated with greater BMD and better microstructure of the peripheral skeleton despite some suggestions of significant deleterious changes in cortical measures in the non-weight bearing radius. Associations were no longer significant after adjustment for BMI or weight, suggesting that the effects of VAT may not have a substantial effect on the skeleton independent of BMI or weight. © 2016 American Society for Bone and Mineral Research.
authors.affiliation: Department of Biostatistics, School of Public Health, Boston University, Boston, MA, USA.
authors.forename: Ching-Ti
authors.initials: CT
authors.lastname: Liu
authors.affiliation: Institute for Aging Research, Hebrew SeniorLife, Boston, MA, USA.
authors.forename: Kerry E
authors.initials: KE
authors.lastname: Broe
authors.affiliation: Department of Biostatistics, School of Public Health, Boston University, Boston, MA, USA.
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: McCaig Institute for Bone and Joint Health, Cumming School of Medicine and Schulich School of Engineering, University of Calgary, Alberta, Canada.
authors.forename: Steven K
authors.initials: SK
authors.lastname: Boyd
authors.affiliation: Department of Biostatistics, School of Public Health, Boston University, Boston, MA, USA.|Framingham Heart Study, Framingham, MA, USA.
authors.forename: L Adrienne
authors.initials: LA
authors.lastname: Cupples
authors.affiliation: Institute for Aging Research, Hebrew SeniorLife, Boston, MA, USA.|Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Marian T
authors.initials: MT
authors.lastname: Hannan
authors.affiliation: Department of Biostatistics, School of Public Health, Boston University, Boston, MA, USA.
authors.forename: Elise
authors.initials: E
authors.lastname: Lim
authors.affiliation: Institute for Aging Research, Hebrew SeniorLife, Boston, MA, USA.|Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Robert R
authors.initials: RR
authors.lastname: McLean
authors.affiliation: Institute for Aging Research, Hebrew SeniorLife, Boston, MA, USA.|Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Samelson
authors.affiliation: Center for Advanced Orthopedic Studies, Beth Israel Deaconess Medical Center, Boston, MA, USA.
authors.forename: Mary L
authors.initials: ML
authors.lastname: Bouxsein
authors.affiliation: Institute for Aging Research, Hebrew SeniorLife, Boston, MA, USA.|Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Douglas P
authors.initials: DP
authors.lastname: Kiel
mesh_terms: D000328:Adult; D001842:Bone and Bones / Q000473:pathology*; D016001:Confidence Intervals; D005260:Female; D006801:Humans; D050152:Intra-Abdominal Fat / Q000473:pathology*; D016018:Least-Squares Analysis; D008297:Male; D008875:Middle Aged; D010024:Osteoporosis / Q000473:pathology*; D012727:Sex Characteristics
keywords: BONE DENSITY; BONE MICROARCHITECTURE; GENERAL POPULATION STUDIES; OSTEOPOROSIS EPIDEMIOLOGY; VISCERAL ADIPOSITY