Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Hong Kong, China.
Jockey Club Centre for Osteoporosis Care and Control, The Chinese University of Hong Kong, Hong Kong, China.
J Am Med Dir Assoc. 2014 Dec;15(12):918-23. doi: 10.1016/j.jamda.2014.07.011. Epub 2014 Sep 24.
To examine whether the inclusion of sarcopenia in prediction models adds any incremental value to fracture risk assessment tool (FRAX).
DESIGN, SETTING, AND PARTICIPANTS: Data from a prospective cohort of 4000 community-dwelling Chinese men and women aged 65 years and older with adjudicated fracture outcomes were analyzed.
At baseline, femoral neck bone mineral density (BMD) was assessed, as were the clinical risk factors included in FRAX, along with additional appendicular skeletal muscle mass, grip strength, and gait speed. Sarcopenia was defined according to the Asian Working Group for Sarcopenia algorithm. Incident fractures were documented during the follow-up period from 2001 to 2013.
Of 4000 participants, 565 experienced at least 1 type of incident fracture and 132 experienced a hip fracture during a follow-up of 10.2 years. Hazard ratios (HRs) for 1-unit increase in FRAX score without BMD in men were 1.12 [95% confidence interval (CI) 1.08-1.16] for all fractures combined and 1.19 (95% CI 1.13-1.27) for hip fracture, and in women were 1.04 (95% CI 1.03-1.06) for all fractures combined and 1.08 (95% CI 1.06-1.11) for hip fracture. Similar to results of the FRAX score without BMD, HRs for 1-unit increase in FRAX score with BMD in men were 1.04 (95% CI 1.03-1.06) for all fractures combined and 1.19 (95% CI 1.13-1.25) for hip fracture, and in women were 1.04 (95% CI 1.03-1.05) for all fractures combined and 1.06 (95% CI 1.05-1.08) for hip fracture. Sarcopenia was significantly associated with all fractures combined (Adjusted HR 1.87; 95% CI 1.30-2.68) and hip fracture (Adjusted HR 2.67; 95% CI 1.46-4.90) in men but not in women. The discriminative values for fracture, as measured by the area under the receiver operating characteristic curve, were 0.60-0.73 and 0.62-0.76 for FRAX without and with BMD, respectively. Adding sarcopenia did not significantly improve the discriminatory capacity over FRAX (P > .05). Using reclassification techniques, sarcopenia significantly enhanced the integrated discrimination improvement by 0.6% to 1.2% and the net reclassification improvement by 7.2% to 20.8% in men, but it did not contribute to predictive accuracy in women.
Sarcopenia added incremental value to FRAX in predicting incident fracture in older Chinese men.
探讨肌少症纳入骨折风险评估工具（FRAX）是否能为骨折风险评估提供额外的增量价值。
设计、地点和参与者：对一项前瞻性队列研究的 4000 名年龄在 65 岁及以上、有明确骨折结局的社区居住的中国男性和女性的数据进行了分析。
在基线时，评估了股骨颈骨密度（BMD），以及 FRAX 中包含的临床危险因素，同时还评估了四肢骨骼肌质量、握力和步速。肌少症根据亚洲肌少症工作组的算法定义。在 2001 年至 2013 年的随访期间记录了新发骨折。
在 4000 名参与者中，565 人至少经历了 1 种类型的新发骨折，132 人经历了髋部骨折，随访时间为 10.2 年。男性中，不包括 BMD 的 FRAX 评分每增加 1 个单位，所有骨折的 HR 为 1.12（95%CI 1.08-1.16），髋部骨折的 HR 为 1.19（95%CI 1.13-1.27），女性中，不包括 BMD 的 FRAX 评分每增加 1 个单位，所有骨折的 HR 为 1.04（95%CI 1.03-1.06），髋部骨折的 HR 为 1.08（95%CI 1.06-1.11）。与不包括 BMD 的 FRAX 评分结果相似，男性中包括 BMD 的 FRAX 评分每增加 1 个单位，所有骨折的 HR 为 1.04（95%CI 1.03-1.06），髋部骨折的 HR 为 1.19（95%CI 1.13-1.25），女性中包括 BMD 的 FRAX 评分每增加 1 个单位，所有骨折的 HR 为 1.04（95%CI 1.03-1.05），髋部骨折的 HR 为 1.06（95%CI 1.05-1.08）。肌少症与所有骨折（调整后的 HR 1.87；95%CI 1.30-2.68）和髋部骨折（调整后的 HR 2.67；95%CI 1.46-4.90）显著相关，但在女性中无显著相关性。骨折的判别值，即接受者操作特征曲线下的面积，分别为 0.60-0.73 和 0.62-0.76，对于不包括和包括 BMD 的 FRAX。肌少症的加入并没有显著提高 FRAX 的判别能力（P>0.05）。使用重新分类技术，肌少症显著提高了男性的综合判别改善度 0.6%至 1.2%，净重新分类改善度 7.2%至 20.8%，但在女性中并未提高预测准确性。
肌少症增加了 FRAX 在预测中国老年男性新发骨折方面的增量价值。
