Table 3. Area under the ROC curve, cutoff, sensitivity, and specificity of the muscle measures/indexes to identify low muscle mass1.
| Variables | Sex | Area under the ROC curve (95%IC) | Cutoff | Sensitivity, % (95%CI) | Specificity, % (95%CI) |
|---|---|---|---|---|---|
| MAMC (cm) | Female | 0.78 (0.70, 0.86)* | ≤22.03 | 65.4 (54.0, 75.7) | 89.4 (76.9, 96.5) |
| Male | 0.76 (0.67, 0.84)* | ≤26.92 | 80.0 (66.3, 90.0) | 61.2 (50.0, 71.6) | |
| AMA (cm2) | Female | 0.78 (0.70, 0.87)* | ≤38.65 | 65.4 (54.0, 75.7) | 89.4 (76.9, 96.5) |
| Male | 0.76 (0.67, 0.84)* | ≤57.68 | 80.0 (66.3, 90.0) | 61.2 (50.0, 71.6) | |
| cAMA (cm2) | Female | 0.78 (0.70, 0.87)* | ≤32.15 | 65.4 (54.0, 75.7) | 89.4 (76.9, 96.5) |
| Male | 0.76 (0.67, 0.84)* | ≤47.68 | 80.0 (66.3, 90.0) | 61.2 (50.0, 71.6) | |
| APMT (mm) | Female | 0.72 (0.63, 0.81)* | ≤18.33 | 72.5 (61.4, 81.9) | 65.2 (49.8, 78.6) |
| Male | 0.81 (0.74, 0.88)* | ≤24.33 | 89.8 (77.8, 96.6) | 60.5 (49.3, 70.8) | |
| CC (cm) | Female | 0.89 (0.84, 0.95)* | ≤35.5 | 76.5 (65.8, 85.2) | 93.6 (82.5, 98.7) |
| Male | 0.85 (0.79, 0.91)* | ≤37.0 | 88.0 (75.7, 95.5) | 69.4 (58.5, 79.0) | |
| PhA (°) | Female | 0.60 (0.50, 0.70)* | ≤5.43 | 46.9 (35.7, 58.3) | 74.5 (59.7, 86.1) |
| Male | 0.55 (0.45, 0.65)* | ≤6.32 | 56.0 (41.3, 70.0) | 59.3 (48.2, 69.8) | |
| BCM (kg) | Female | 0.78 (0.70, 0.86)* | ≤17.6 | 75.3 (64.5, 84.2) | 66.0 (50.7, 79.1) |
| Male | 0.76 (0.68, 0.84)* | ≤29.2 | 90.0 (78.2, 96.7) | 51.2 (40.1, 62.1) | |
| BCMI (kg/m2) | Female | 0.73 (0.64, 0.82)* | ≤7.2 | 70.4 (59.2, 80.0) | 68.1 (52.9, 80.9) |
| Male | 0.65 (0.56, 0.74)* | ≤8.67 | 54.0 (39.3, 68.2) | 74.4 (63.9, 83.2) | |
| FFMBCM (kg) | Female | 0.79 (0.71, 0.87)* | ≤31.7 | 70.4 (59.2, 80.0) | 72.3 (57.4, 84.4) |
| Male | 0.77 (0.69, 0.85)* | ≤49.9 | 94.0 (83.5, 98.7) | 51.2 (40.1, 62.1) | |
| FFMBCM (%) | Female | 0.36 (0.27, 0.46) | - | - | - |
| Male | 0.34 (0.24, 43) | - | - | - | |
| FFMIBCM (kg/m2) | Female | 0.73 (0.65, 0.82)* | ≤13.29 | 75.3 (64.5, 84.2) | 63.8 (48.5, 77.3) |
| Male | 0.66 (0.56, 0.75)* | ≤15.24 | 54.0 (39.3, 68.2) | 74.4 (63.9, 83.2) | |
| pFFM (kg) | Female | 0.96 (0.93, 0.99)* | ≤35.02 | 87.6 (78.5, 93.9) | 93.6 (82.5, 98.7) |
| Male | 0.94 (0.89, 0.98)* | ≤46.42 | 95.9 (86.0, 99.5) | 85.9 (76.6, 92.5) | |
| pFFM (%) | Female | 0.26 (0.18, 0.35) | - | - | - |
| Male | 0.42 (0.32, 0.52) | - | - | - | |
| pFFMI (kg/m2) | Female | 0.83 (0.75, 0.90)* | ≤13.68 | 64.2 (52.8, 74.6) | 89.4 (76.9, 96.5) |
| Male | 0.86 (0.79, 0.92)* | ≤16.85 | 87.8 (75.2, 95.4) | 76.5 (66.0, 85.0) | |
| AFFM (kg) | Female | 0.96 (0.94, 0.99)* | ≤15.87 | 90.1 (81.5, 95.6) | 95.7 (85.5, 99.5) |
| Male | 0.94 (0.89, 0.98)* | ≤21.43 | 98.0 (89.4, 99.9) | 83.7 (74.2, 90.8) |
1ALM by Dual energy X-ray absorptiometry analysis, with ALM<15kg for women and ALM <20kg for men [10].
*p ≤ 0.05. FFMBCM (%) and pFFM (%): AUC < 0.50 (it is not possible to define a cutoff). AFFM, appendicular fat free mass; ALM, appendicular lean mass; AMA, arm muscle area; APTM, adductor pollicis muscle thickness; BCM, body cell mass; BCMI, body cell mass index; cAMA, corrected arm muscle area; CC, calf circumference; FFMBCM, fat free mass by body composition monitor; FFMIBCM, fat free mass index by body composition monitor; MAMC, mid-arm muscle circumference; pFFM, predicted fat free mass; pFFMI, predicted fat free mass index; PhA, phase angle; ROC, receiver operating characteristic. PhA, BCM, BCMI, FFMBCM, FFMIBCM, pFFM, pFFMI and AFFM measures by bioelectrical impedance. AFFM by Sergi equation [20] and pFFM by Bellafronte equation [22]. FMBCM by bioelectrical impedance from body composition monitor (Fresenius Medical Care).