Supplementary Material for: Probable Sarcopenia, Obesity, and Risk of All-Cause Mortality: A Pooled Analysis of 4,612 Participants

Introduction: Conflicting evidence exists concerning whether having sarcopenic obesity has additive mortality risk over having only sarcopenia or obesity. We examined the independent and combined associations of obesity and probable sarcopenia with all-cause mortality. Methods: The pooled analysis included three large, harmonized datasets (Health 2000 Survey; Health, Aging and Body Composition Study; Longitudinal Aging Study Amsterdam) with mortality follow-up data on individuals aged 70 years and over at baseline (n = 4,612). Obesity indicators included body mass index and waist circumference, and probable sarcopenia was defined based on grip strength. The mixed effects Cox model was used for statistical analyses, adjusting for age, sex, marital status, education, race, physical activity, alcohol consumption, smoking, and baseline diseases. Results: Risk of death increased for those having probable sarcopenia only (hazard ratio [HR]: 1.61, 95% confidence interval [CI]: 1.39–1.85) or probable sarcopenia with obesity (HR: 1.36, 95% CI: 1.13–1.64) but not for the obese-only group (HR: 0.92, 95% CI: 0.85–1.01), when compared to non-obese non-sarcopenic individuals. The results were similar regardless of adjustments for covariates or different obesity criteria applied. Conclusion: Probable sarcopenia, whether combined with obesity or not, is associated with increased mortality. Obesity did not increase mortality among older adults. Maintaining muscle strength and identifying older adults at risk of sarcopenia is important for the prevention of premature mortality.

引言：关于肌肉减少性肥胖（sarcopenic obesity）是否较单纯肌肉减少症（sarcopenia）或单纯肥胖额外增加死亡风险，目前存在相互矛盾的研究证据。本研究旨在探讨肥胖与可能的肌肉减少症分别及联合与全因死亡率（all-cause mortality）的独立及联合关联。方法：本汇总分析纳入三项经过标准化整合的大型数据集——健康2000调查（Health 2000 Survey）、健康、衰老与身体构成研究（Health, Aging and Body Composition Study）、阿姆斯特丹纵向衰老研究（Longitudinal Aging Study Amsterdam），共纳入基线时年龄≥70岁的受试者4612名，所有受试者均带有死亡随访数据。肥胖评估指标包括体重指数（body mass index）与腰围（waist circumference），可能的肌肉减少症依据握力（grip strength）进行定义。本研究采用混合效应Cox模型（mixed effects Cox model）开展统计分析，校正了年龄、性别、婚姻状况、教育水平、种族、体力活动、饮酒、吸烟及基线疾病等混杂因素。结果：与非肥胖非肌肉减少症受试者相比，仅罹患可能肌肉减少症者（风险比[HR]=1.61，95%置信区间[CI]=1.39~1.85）或同时合并可能肌肉减少症与肥胖者（HR=1.36，95%CI=1.13~1.64）的死亡风险均显著升高；但仅肥胖组未观察到死亡风险升高（HR=0.92，95%CI=0.85~1.01）。无论是否校正混杂因素，或采用不同的肥胖判定标准，所得结果均保持一致。结论：无论是否合并肥胖，可能的肌肉减少症均与死亡风险升高显著相关；而肥胖并未使老年人群的死亡风险升高。维持肌肉力量、识别存在肌肉减少症风险的老年个体，对于预防过早死亡具有重要意义。