Department of Radiology, Beijing Jishuitan Hospital, National Center for Orthopaedics, Beijing, China.
JST Sarcopenia Research Center, Beijing Research Institute of Traumatology and Orthopaedics, Beijing, China.
J Cachexia Sarcopenia Muscle. 2023 Aug;14(4):1824-1835. doi: 10.1002/jcsm.13261. Epub 2023 May 19.
Mortality following hip fracture is high and incompletely understood. We hypothesize that hip musculature size and quality are related to mortality following hip fracture. This study aims to investigate the associations of hip muscle area and density from hip CT with death following hip fracture as well as assess the dependence of this association on time after hip fracture.
In this secondary analysis of the prospectively collected CT images and data from the Chinese Second Hip Fracture Evaluation, 459 patients were enrolled between May 2015 and June 2016 and followed up for a median of 4.5 years. Muscle cross-sectional area and density were measured of the gluteus maximus (G.MaxM) and gluteus medius and minimus (G.Med/MinM) and aBMD of the proximal femur. The Goutallier classification (GC) was used for qualitatively assessing muscle fat infiltration. Separate Cox models were used to predict mortality risk adjusted for covariates.
At the end of the follow-up, 85 patients were lost, 81 patients (64% women) had died, and 293 (71% women) survived. The mean age of non-surviving patients at death (82.0 ± 8.1 years) was higher than that of the surviving patients (74.4 ± 9.9 years). The Parker Mobility Score and the American Society of Anesthesiologists scores of the patients that died were respectively lower and higher compared to the surviving patients. Hip fracture patients received different surgical procedures, and no significant difference in the percentage of hip arthroplasty was observed between the dead and the surviving patients (P = 0.11). The cumulative survival was significantly lower for patients with low G.MaxM area and density and low G.Med/MinM density, independent of age and clinical risk scores. The GC grades were not associated with the mortality after hip fracture. Muscle density of both G.MaxM (adj. HR 1.83; 95% CI, 1.06-3.17) and G.Med/MinM (adj. HR 1.98; 95% CI, 1.14-3.46) was associated with mortality in the 1st year after hip fracture. G.MaxM area (adj. HR 2.11; 95% CI, 1.08-4.14) was associated with mortality in the 2nd and later years after hip fracture.
Our results for the first time show that hip muscle size and density are associated with mortality in older hip fracture patients, independent of age and clinical risk scores. This is an important finding to better understand the factors contributing to the high mortality in older hip fracture patients and to develop better future risk prediction scores that include muscle parameters.
髋部骨折后的死亡率很高，且其发病机制尚不完全清楚。我们假设髋部肌肉的大小和质量与髋部骨折后的死亡率有关。本研究旨在探讨髋部 CT 检查中髋部肌肉面积和密度与髋部骨折后死亡的关系，并评估这种关联对髋部骨折后时间的依赖性。
这是对前瞻性收集的 CT 图像和来自中国第二次髋部骨折评估的数据进行的二次分析，共纳入了 2015 年 5 月至 2016 年 6 月期间的 459 例患者，中位随访时间为 4.5 年。测量了臀大肌（G.MaxM）、臀中肌和臀小肌（G.Med/MinM）的肌肉横截面积和密度以及股骨近端的 aBMD。使用 Goutallier 分级（GC）对肌肉脂肪浸润进行定性评估。分别使用 Cox 模型对调整了协变量的死亡率风险进行预测。
在随访结束时，85 例患者失访，81 例（64%为女性）患者死亡，293 例（71%为女性）患者存活。死亡患者的平均年龄（82.0±8.1 岁）高于存活患者（74.4±9.9 岁）。与存活患者相比，死亡患者的 Parker 活动能力评分和美国麻醉师协会评分分别较低和较高。髋部骨折患者接受了不同的手术治疗，但死亡患者和存活患者之间的髋关节置换术百分比无显著差异（P=0.11）。无论年龄和临床风险评分如何，低 G.MaxM 面积和密度以及低 G.Med/MinM 密度的患者的累积生存率均显著降低。GC 分级与髋部骨折后死亡率无关。髋部骨折后 1 年内，G.MaxM（调整后 HR 1.83；95%CI，1.06-3.17）和 G.Med/MinM（调整后 HR 1.98；95%CI，1.14-3.46）的肌肉密度与死亡率相关。髋部骨折后 2 年及以后，G.MaxM 面积（调整后 HR 2.11；95%CI，1.08-4.14）与死亡率相关。
我们的研究结果首次表明，髋部肌肉的大小和密度与老年髋部骨折患者的死亡率相关，与年龄和临床风险评分无关。这一重要发现有助于更好地理解导致老年髋部骨折患者高死亡率的因素，并开发更好的未来风险预测评分，包括肌肉参数。
