Nutrition and Dietetic Service, Cancer Hospital Unit I, National Cancer Institute José Alencar Gomes da Silva, Rio de Janeiro, Brazil; Graduation Program in Nutrition, Food and Health, Nutrition Institute, Rio de Janeiro State University, Rio de Janeiro, Brazil.
Post-graduate Program in Health and Behavior, Catholic University of Pelotas, Pelotas, Brazil.
Clin Nutr. 2020 Feb;39(2):484-491. doi: 10.1016/j.clnu.2019.02.026. Epub 2019 Feb 22.
BACKGROUND & AIMS: We aimed to explore the determinants of muscle fat infiltration and to investigate whether myosteatosis, assessed as muscle fat infiltration percentage (%MFI) and muscle attenuation from computed tomography (CT), is associated with frailty in a group of patients with colorectal cancer (CRC).
Cross sectional study including CRC patients. CT scan of the third lumbar vertebra was used to quantify body composition and the degree of %MFI (reported as percentage of fat within muscle area). Frailty was defined by Fried et al. (2001) as the presence of more than 3 criteria: unintentional weight loss, self-reported exhaustion, weakness (low handgrip strength), slow walking speed (gait speed) and low physical activity. Obesity was defined according to sex-and-age-specific body fat percentage (%BF) cutoff.
A sample of 184 patients (age 60 ± 11 years; 58% men; 29% of patients with frailty) was studied. The sample was divided according to tertiles of MFI% (1st tertile 0 to 2.89%, n = 60; 2nd tertile ≥ 3.9-8.19%, n = 64; 3rd tertile ≥ 8.2-26%, n = 60). Age, females, body mass index, %BF, subcutaneous and visceral adipose tissue and the proportion of patients with frailty were significantly higher in the 3rd %MFI tertile. Phase angle and muscle attenuation were significantly lower in the 3rd %MFI tertile. The determinants of %MFI (r = 0.49), which was log transformed due to its normal distribution, were %BF (β = 0.54; e = 1.72; 95% CI: 0.032 to 0.051; P < 0.01), age (β = 0.34; e = 1.40; 95% CI: 0.016 to 0.032; P < 0.01) and gait speed (β = -0.12; e = 0.87; 95% CI: -0.84 to -0.001; P = 0.049). In addition, in obese patients (n = 74) presenting 4 or 5 frailty criteria increased the chance of having higher %MFI and lower muscle attenuation, after adjustment for sex, age and comorbidities when compared to none or 1 criteria.
In a sample of CRC patients, %BF and gait speed were the determinants of %MFI. In addition, markers of myostetatosis were associated with frailty in the obese patients.
我们旨在探讨肌肉脂肪浸润的决定因素，并研究肌肉脂肪浸润百分比（%MFI）和计算机断层扫描（CT）评估的肌肉衰减是否与一组结直肠癌（CRC）患者的虚弱有关。
纳入 CRC 患者的横断面研究。使用第三腰椎的 CT 扫描来定量身体成分和 %MFI 程度（报告为肌肉区域内的脂肪百分比）。虚弱根据 Fried 等人（2001 年）的定义确定（存在 3 项以上标准：非故意体重减轻、自我报告的疲劳、虚弱（握力低）、步行速度慢（步态速度）和体力活动低）。肥胖根据性别和年龄特异性体脂肪百分比（%BF）切点定义。
研究了 184 名患者（年龄 60±11 岁；58%为男性；29%的患者虚弱）的样本。根据 MFI%的三分位数（第 1 三分位数 0 至 2.89%，n=60；第 2 三分位数 3.9-8.19%，n=64；第 3 三分位数 8.2-26%，n=60）对样本进行了分组。第 3 个%MFI 三分位数的年龄、女性、体重指数、%BF、皮下和内脏脂肪组织以及虚弱患者的比例明显更高。第 3 个%MFI 三分位数的相位角和肌肉衰减明显较低。由于其正态分布，对 %MFI（r=0.49）进行了对数转换，%BF（β=0.54；e=1.72；95%CI：0.032 至 0.051；P<0.01）、年龄（β=0.34；e=1.40；95%CI：0.016 至 0.032；P<0.01）和步态速度（β=-0.12；e=0.87；95%CI：-0.84 至-0.001；P=0.049）是 %MFI 的决定因素。此外，在肥胖患者（n=74）中，与无 1 项或 1 项虚弱标准相比，存在 4 项或 5 项虚弱标准会增加出现更高的%MFI 和更低的肌肉衰减的机会，在调整性别、年龄和合并症后。
在 CRC 患者样本中，%BF 和步态速度是 %MFI 的决定因素。此外，肌肉脂肪化的标志物与肥胖患者的虚弱有关。
