Department of Medicine, Surgery and Neuroscience, Unità Operativa Complessa (UOC) Endocrinology, University of Siena, Siena, Italy.
Department of Medical Biotechnologies, University of Siena, Siena, Italy.
Front Endocrinol (Lausanne). 2024 Jul 5;15:1369584. doi: 10.3389/fendo.2024.1369584. eCollection 2024.
Bioelectrical impedance analysis (BIA) is the most used tool in clinical practice to evaluate body composition in patients with obesity. The skeletal muscle index (SMI) defined by BIA has been proposed for the identification of sarcopenia, but there are currently no univocal cutoffs for this condition. In this study, we aimed: 1) to determine the prevalence of sarcopenia in patients with severe obesity using the current cutoffs of SMI; 2) to define new specific cutoffs; 3) to validate the new cutoffs; and 4) to re-determine the prevalence of sarcopenia.
A total of 300 patients, 74% women and 26% men (mean age = 42.6 ±; 9 years), with morbid obesity (mean BMI = 46.7 ±; 6.5 kg/m) followed by the Unit of Endocrinology from January 2014 to December 2020 were retrospectively evaluated. SMI was calculated as the skeletal muscle mass normalized for squared height through the BIA equation by Janssen et al.
The prevalence of sarcopenic obesity calculated using the cutoff points reported by De Rosa et al. (7.3 kg/h for women and 9.5 kg/h for men) was 2.3%. The prevalence of sarcopenia was calculated using the new cutoffs: with the cutoff obtained from the standard deviation method (8.2 kg/h for women and 10.2 kg/h for men), a prevalence of 14.7% was observed, whereas the prevalence reached 47.6% when using the cutoff calculated through the -means unsupervised cluster (9.2 kg/h for women and 11.3 kg/h for men). The new cutoffs were validated with a second sample consisting of 300 patients with morbid obesity (BMI = 44.9 ±; 6.7 kg/m): the rate of sarcopenic patients was still higher than that observed in the training cohort (56%). After the matching procedure (by BMI and age), the rates of sarcopenic patients were similar in both groups (50.2% in the validation group and 53% in the training group, p
The new cutoffs calculated with cluster analysis could better identify sarcopenia in morbidly obese patients. However, further studies are needed to validate these cutoffs in different patient cohorts.
生物电阻抗分析（BIA）是临床实践中评估肥胖患者身体成分最常用的工具。通过 BIA 定义的骨骼肌指数（SMI）已被提议用于识别肌少症，但目前对于这种情况还没有明确的界限。在这项研究中，我们的目的是：1）使用当前的 SMI 截止值确定严重肥胖患者中肌少症的患病率；2）定义新的特定截止值；3）验证新的截止值；4）重新确定肌少症的患病率。
回顾性评估了 2014 年 1 月至 2020 年 12 月期间内分泌科收治的 300 名患者，其中 74%为女性，26%为男性（平均年龄为 42.6 ± 9 岁），体重指数（BMI）为 46.7 ± 6.5 kg/m。通过 Janssen 等人的 BIA 方程，将骨骼肌质量归一化为身高的平方，计算 SMI。
使用 De Rosa 等人报道的截止值（女性 7.3 kg/h，男性 9.5 kg/h）计算出的肥胖性肌少症的患病率为 2.3%。使用新的截止值计算肌少症的患病率：使用标准差法得到的截止值（女性 8.2 kg/h，男性 10.2 kg/h），观察到的患病率为 14.7%，而使用无监督聚类均值法计算的截止值（女性 9.2 kg/h，男性 11.3 kg/h）时，患病率达到 47.6%。通过包含 300 名肥胖症患者（BMI = 44.9 ± 6.7 kg/m）的第二个样本对新的截止值进行了验证：肌少症患者的比例仍然高于训练队列中的比例（56%）。经过 BMI 和年龄匹配后，两个队列中肌少症患者的比例相似（验证组为 50.2%，训练组为 53%，p
