Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia.
National Centre for Epidemiology and Population Health, Australian National University, Canberra, Australia.
Calcif Tissue Int. 2020 Jul;107(1):10-17. doi: 10.1007/s00223-020-00698-z. Epub 2020 Apr 28.
This study aims to assess whether older adults with low muscle mass or strength, in the presence of obesity, have an increased risk of knee (TKR) and hip replacement (THR) over 13 years. 1082 community-dwelling older adults (51% women; mean age 62.9 ± 7.5 years) were studied at baseline and multiple time points over 13 years. The incidence of TKR and THR was determined by data linkage to National Joint Replacement Registry. Appendicular lean and fat mass were measured using DXA. Lower-limb muscle strength (LMS) was assessed by dynamometer. Low muscle mass and strength were defined as the lowest sex-specific tertiles for appendicular lean mass (adjusted for height and total body fat mass) and lower-limb strength, respectively. Obesity was defined as the highest sex-specific tertile for total body fat mass. Competing risk regression models were used to estimate the sub-distribution hazard ratio (SHR) for TKR and THR. Over 13 years of follow-up, 6.8% (n = 74/1082) of the participants had a TKR and 4.7% (n = 50/1066) had THR. Participants with the combination of obesity and low muscle strength (SHR 3.36, 95% CI 1.50, 7.53) but low muscle mass (SHR 1.11, 95% CI 0.52, 2.40) had a significantly increased risk of TKR, compared to individuals with neither obesity nor low muscle mass/strength. However, obesity with low muscle strength did not lead to a significantly greater risk of TKR compared to having low muscle strength or obesity alone. There was no evidence for an association between obesity with low muscle mass or strength and THR (all p > 0.05). This finding suggests that combining muscle and fat assessments to predict the future risk of TKR is no better than each condition on its own.
本研究旨在评估肥胖伴低肌肉量或低肌肉力量的老年人，其在 13 年内膝关节（TKR）和髋关节（THR）置换的风险是否增加。研究共纳入了 1082 名社区居住的老年人（51%为女性；平均年龄 62.9±7.5 岁），并在 13 年内的多个时间点进行了研究。通过与国家关节置换登记处的数据链接确定 TKR 和 THR 的发生率。使用 DXA 测量四肢瘦体重和脂肪量。通过测力计评估下肢肌肉力量（LMS）。低肌肉量和低肌肉力量定义为根据身高和全身脂肪质量调整后的四肢瘦体重的最低性别特异性三分位数（分别为下肢力量）。肥胖定义为全身脂肪质量的最高性别特异性三分位数。使用竞争风险回归模型估计 TKR 和 THR 的亚分布风险比（SHR）。在 13 年的随访期间，有 6.8%（n=74/1082）的参与者发生了 TKR，4.7%（n=50/1066）发生了 THR。与既没有肥胖也没有低肌肉量/力量的参与者相比，肥胖且低肌肉力量（SHR 3.36，95%CI 1.50，7.53）的参与者 TKR 风险显著增加，但低肌肉量（SHR 1.11，95%CI 0.52，2.40）。然而，肥胖伴低肌肉力量与单独存在低肌肉力量或肥胖相比，并未导致 TKR 的风险显著增加。肥胖伴低肌肉量或低肌肉力量与 THR 之间没有关联的证据（所有 p 值>0.05）。这一发现表明，将肌肉和脂肪评估结合起来预测 TKR 的未来风险并不优于每种情况单独评估。
