Gandham, A and Zengin, A and Bonham, MP and Winzenberg, T and Balogun, S and Wu, F and Aitken, D and Cicuttini, F and Ebeling, PR and Jones, G and Scott, D, Incidence and predictors of fractures in older adults with and without obesity defined by body mass index versus body fat percentage, Bone, 140 Article 115546. ISSN 8756-3282 (2020) [Refereed Article]
© 2020 Elsevier Inc. All rights reserved.
Methods: 1,099 older adults (mean ± standard deviation age = 63.0 ± 7.5) years, participated in this prospective cohort study. Obesity status at baseline was defined by BMI (≥30 kg/m2) obtained by anthropometry and body fat percentage (≥30% for men and ≥40% for women) assessed by dual-energy X-ray absorptiometry (DXA). Total hip and lumbar spine areal bone mineral density (aBMD) were assessed by DXA up to five years. Incident fractures were self-reported up to 10 years.
Results: Prevalence of obesity was 28% according to BMI and 43% according to body fat percentage. Obese older adults by BMI, but not body fat percentage, had significantly higher aBMD at the total hip and spine compared with non-obese (both p-value<0.05). Obese older adults by body fat percentage had significantly higher likelihood of all incident fractures (OR: 1.71; CI:1.08, 2.71) and non-vertebral fractures (OR: 1.88; CI:1.16, 3.04) compared with non-obese after adjusting for confounders. Conversely, obese older adults by BMI had a significantly lower likelihood (OR: 0.54; CI:0.31, 0.94) of non-vertebral fractures although this was no longer significant after adjustment for total hip aBMD (all p-value > 0.05). Mediation analysis confirmed that aBMD meditated the effects of BMI, but not body fat percentage, on all incident fractures. Higher baseline falls risk score was the only consistent predictor of increased likelihood of incident fracture in obese individuals only, according to both BMI and body fat percentage (both p-value<0.05).
Conclusions: Obesity defined by body fat percentage is associated with increased likelihood of incident fractures in community-dwelling older adults, whereas those who are obese according to BMI have reduced likelihood of incident fracture which appears to be explained by higher aBMD. Falls risk assessment may improve identification of obese older adults at increased risk of incident fractures.
|Item Type:||Refereed Article|
|Keywords:||aging, bone, fracture, obesity, older adults|
|Research Division:||Biomedical and Clinical Sciences|
|Research Group:||Clinical sciences|
|Research Field:||Rheumatology and arthritis|
|Objective Group:||Clinical health|
|Objective Field:||Clinical health not elsewhere classified|
|UTAS Author:||Winzenberg, T (Professor Tania Winzenberg)|
|UTAS Author:||Balogun, S (Dr Saliu Balogun)|
|UTAS Author:||Wu, F (Dr Feitong Wu)|
|UTAS Author:||Aitken, D (Associate Professor Dawn Aitken)|
|UTAS Author:||Jones, G (Professor Graeme Jones)|
|UTAS Author:||Scott, D (Mr David Scott)|
|Web of Science® Times Cited:||10|
|Deposited By:||Menzies Institute for Medical Research|
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