title: Impact of Competing Risk of Mortality on Association of Weight Loss With Risk of Central Body Fractures in Older Men: A Prospective Cohort Study.
abstract: To determine the association of weight loss with risk of clinical fractures at the hip, spine, and pelvis (central body fractures [CBFs]) in older men with and without accounting for the competing risk of mortality, we used data from 4523 men (mean age 77.5 years). Weight change between baseline and follow-up (mean 4.5 years between examinations) was categorized as moderate loss (loss ≥10%), mild loss (loss 5% to <10%), stable (<5% change) or gain (gain ≥5%). Participants were contacted every 4 months after the follow-up examination to ascertain vital status (deaths verified by death certificates) and ask about fractures (confirmed by radiographic reports). Absolute probability of CBF by weight change category was estimated using traditional Kaplan-Meier method and cumulative incidence function accounting for competing mortality risk. Risk of CBF by weight change category was determined using conventional Cox proportional hazards regression and subdistribution hazards models with death as a competing risk. During an average of 8 years, 337 men (7.5%) experienced CBF and 1569 (34.7%) died before experiencing this outcome. Among men with moderate weight loss, CBF probability was 6.8% at 5 years and 16.9% at 10 years using Kaplan-Meier versus 5.7% at 5 years and 10.2% at 10 years using a competing risk approach. Men with moderate weight loss compared with those with stable weight had a 1.6-fold higher adjusted risk of CBF (HR 1.59; 95% CI, 1.06 to 2.38) using Cox models that was substantially attenuated in models accounting for competing mortality risk and no longer significant (subdistribution HR 1.16; 95% CI, 0.77 to 1.75). Results were similar in analyses substituting hip fracture for CBF. Older men with weight loss who survive are at increased risk of CBF, including hip fracture. However, ignoring the competing mortality risk among men with weight loss substantially overestimates their long-term fracture probability and relative fracture risk. © 2016 American Society for Bone and Mineral Research.
authors.affiliation: Department of Medicine, University of Minnesota, Minneapolis, MN, USA.|Division of Epidemiology & Community Health, School of Public Health, University of Minnesota, Minneapolis, MN, USA.|Center for Chronic Disease Outcomes Research, VA Health Care System, Minneapolis, MN, USA.
authors.forename: Kristine E
authors.initials: KE
authors.lastname: Ensrud
authors.affiliation: California Pacific Medical Center Research Institute, San Francisco, CA, USA.
authors.forename: Stephanie L
authors.initials: SL
authors.lastname: Harrison
authors.affiliation: Department of Epidemiology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, PA, USA.
authors.forename: Jane A
authors.initials: JA
authors.lastname: Cauley
authors.affiliation: Division of Epidemiology & Community Health, School of Public Health, University of Minnesota, Minneapolis, MN, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Langsetmo
authors.affiliation: HealthPartners Institute, Bloomington, MN, USA.|Division of Health Policy and Management, University of Minnesota, Minneapolis, MN, USA.
authors.forename: John T
authors.initials: JT
authors.lastname: Schousboe
authors.affiliation: Department of Family Medicine and Public Health, University of California, San Diego, La Jolla, CA, USA.
authors.forename: Deborah M
authors.initials: DM
authors.lastname: Kado
authors.affiliation: Department of Family Medicine, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: Margaret L
authors.initials: ML
authors.lastname: Gourlay
authors.affiliation: Department of Epidemiology, Boston University, Boston, MA, USA.
authors.forename: Jennifer G
authors.initials: JG
authors.lastname: Lyons
authors.affiliation: Department of Epidemiology, Boston University, Boston, MA, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Fredman
authors.affiliation: Division of Endocrinology and Diabetes, Università Campus Bio-Medico di Roma, Rome, Italy.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Napoli
authors.affiliation: Deparment of Medicine, University of California, Los Angeles, Los Angeles, CA, USA.
authors.forename: Carolyn J
authors.initials: CJ
authors.lastname: Crandall
authors.affiliation: Division of Preventive Medicine, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA.
authors.forename: Cora E
authors.initials: CE
authors.lastname: Lewis
authors.affiliation: Bone and Mineral Unit, Oregon Health & Science University, Portland, OR, USA.
authors.forename: Eric S
authors.initials: ES
authors.lastname: Orwoll
authors.affiliation: Department of Medicine, Stanford University, Stanford, CA, USA.
authors.forename: Marcia L
authors.initials: ML
authors.lastname: Stefanick
authors.affiliation: California Pacific Medical Center Research Institute, San Francisco, CA, USA.
authors.forename: Peggy M
authors.initials: PM
authors.lastname: Cawthon
mesh_terms: D000368:Aged; D050723:Fractures, Bone / Q000453:epidemiology* / Q000401:mortality* / Q000503:physiopathology; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D011336:Probability; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D015431:Weight Loss / Q000502:physiology*
keywords: CENTRAL BODY FRACTURES; MORTALITY; OLDER MEN; WEIGHT CHANGE