Division of Geriatrics, Department of Internal Medicine, Istanbul Medical School, Istanbul University, Capa, Istanbul, Turkey.
Aging Clin Exp Res. 2023 Oct;35(10):2089-2099. doi: 10.1007/s40520-023-02498-5. Epub 2023 Jul 24.
Probable sarcopenia is a predictor of functional limitation in older adults. However, whether standard thresholds recommended by guides, or population-specific thresholds better predict impairment in functionality is an issue that needs to be enlightened. We aimed to study the associations of probable sarcopenia identified by the use of EWGSOP2 and population-specific thresholds with deterioration in functionality at follow-up and give prevalences of probable sarcopenia with different thresholds in older outpatients admitted to a tertiary health center.
In this retrospective, longitudinal follow-up study, we assessed handgrip strength (HGS) at the admission with a Jamar hand-dynamometer and diagnosed probable sarcopenia with standard and population-specific thresholds, i.e., 27 kg/16 kg, and 35 kg/20 kg in males/females, respectively. We evaluated activities of daily living (ADL) and instrumental ADL (IADL), with Katz and Lawton scales, at the admission and follow-up. To study whether probable sarcopenia was a predictor of impaired functionality, we defined two models for Cox regression analysis. We performed adjustments for age, sex, and nutritional status (assessed by Mini-Nutritional Assessment-Short Form) in Model 1 and defined Model 2 by adding low gait speed and frailty to the variables in Model 1.
Among a total of 1970 patients, 195 had follow-up of median 560 days. The mean age was 75.5 ± 5.5, and 142 (72.8%) were female. In the basal evaluation, the prevalences of probable sarcopenia defined by the standard cut-offs and by population-specific cut-offs were 8.7% and 35.4%, respectively. In univariate analyses (Kaplan-Meier log-rank test), probable sarcopenia by population-specific cut-offs, but not EWGSOP2-cut-offs, was associated with deteriorations in both ADL (p = 0.04) and IADL (p < 0.001). In multivariate analyses, only the probable sarcopenia identified by population-specific cut-offs was independently associated with impairment in IADL in both models [HR (95%CI) = 1.88 (1.07-3.30), and 1.9 (1.04-3.6); for Model 1 and Model 2, respectively)].
Our findings suggested that the definition of probable sarcopenia identified by not standard, but population-specific thresholds more reliably predicted longitudinal deterioration of functionality in older outpatients. This finding might be considered as evidence supporting the use of population-specific cut-offs when the concern is sarcopenia diagnosis.
疑似肌肉减少症是老年人功能受限的预测因素。然而，指南推荐的标准阈值或人群特异性阈值是否能更好地预测功能障碍仍有待阐明。我们旨在研究使用 EWGSOP2 和人群特异性阈值确定的疑似肌肉减少症与随访时功能恶化的关系，并给出在三级保健中心就诊的老年门诊患者中不同阈值下疑似肌肉减少症的患病率。
在这项回顾性、纵向随访研究中，我们使用 Jamar 握力计在入院时评估握力（HGS），并使用标准和人群特异性阈值诊断疑似肌肉减少症，即男性分别为 27kg/16kg 和女性分别为 35kg/20kg。我们在入院和随访时使用 Katz 和 Lawton 量表评估日常生活活动（ADL）和工具性日常生活活动（IADL）。为了研究疑似肌肉减少症是否是功能受损的预测因素，我们定义了两个 Cox 回归分析模型。在模型 1 中，我们调整了年龄、性别和营养状况（通过迷你营养评估-简短表格评估），在模型 2 中，我们在模型 1 中的变量中增加了低步态速度和脆弱性。
在总共 1970 名患者中，有 195 名患者随访中位数为 560 天。平均年龄为 75.5±5.5 岁，142 名（72.8%）为女性。在基线评估中，使用标准截止值和人群特异性截止值定义的疑似肌肉减少症的患病率分别为 8.7%和 35.4%。在单变量分析（Kaplan-Meier 对数秩检验）中，人群特异性截止值确定的疑似肌肉减少症，但不是 EWGSOP2 截止值，与 ADL（p=0.04）和 IADL（p<0.001）恶化相关。在多变量分析中，只有人群特异性截止值确定的疑似肌肉减少症与 IADL 受损独立相关，两个模型中均如此[风险比（95%CI）=1.88（1.07-3.30）和 1.9（1.04-3.6）；模型 1 和模型 2 分别]。
我们的研究结果表明，使用非标准但人群特异性的截止值定义的疑似肌肉减少症与老年门诊患者功能的纵向恶化更可靠相关。这一发现可能被认为是支持在关注肌肉减少症诊断时使用人群特异性截止值的证据。
