Table 1. Basic characteristics of the study subjects
Parameters
|
Total
Mean ± SD
|
Female, No (%), 17 (53)
Median (IQR)
|
Male, No (%), 15 (47)
Median (IQR)
|
Asymp Sig.(2-tailed)
|
Total protein, g/dL
|
6.68 ± 0.54
|
6.60(6.35-6.95)
|
6.80(6.60-7.10)
|
0.264
|
Albumin, g/dL
|
3.69 ± 0.60
|
3.80(2.85-4.05)
|
3.70(3.40-4.40)
|
0.325
|
BUN, mg/dL
|
69.47 ± 16.96
|
72.00(58.50-85.50)
|
61.00(52.00-81.00)
|
0.242
|
Creatinine, mg/dL
|
9.85 ± 2.67
|
8.80(7.00-10.10)
|
11.40(9.70-12.30)
|
0.026
|
Cholesterol, mg/dL
|
166.09 ± 50.91
|
163.00(127.00-212.50
|
153.00(123.00-198.00)
|
0.664
|
Triglyceride, mg/dL
|
176.63 ± 109.77
|
148.00(78.50-245.50)
|
151.00(106.00-265.00)
|
0.835
|
Age, years
|
61.97 ± 13.44
|
62.00(50.50-68.00)
|
65.00(58.00-76.00)
|
0.316
|
Height, cm
|
161.82 ± 7.58
|
156.00(152.75-160.50)
|
168.00(164.00-172.00)
|
<0.001
|
DBW, kg
|
57.57 ± 9.79
|
51.70(48.50-56.65)
|
61.00(55.8-68.8)
|
0.002
|
BMI, kg/m2
|
21.87 ± 2.87
|
21.30(19.10-23.60)
|
22.10(20.10-23.10)
|
0.428
|
TSFT, mm
|
21.55 ± 8.95
|
23.00(20.50-29.15)
|
16.50(12.00-24.3)
|
0.070
|
MAC, cm
|
26.02 ± 2.88
|
26.00(23.45-27.50)
|
27.00(24.00-28.50)
|
0.233
|
MAMC, cm
|
19.25 ± 2.75
|
18.41(16.12-19.45)
|
20.37(18.82-22.55)
|
0.003
|
MAFA, mm2
|
2444.75 ± 1030.23
|
2620.74(2167.35-3221.64)
|
1901.20(1355.87-2938.47)
|
0.180
|
MAMA, mm2
|
3009.16 ± 866.64
|
2697.30(2069.32-3012.24)
|
3303.57(2819.70-4047.15)
|
0.003
|
cMAMA, mm2
|
2206.04 ± 772.66
|
2047.30(1419.32-2362.24)
|
2303.57(1819.70-3047.15)
|
0.073
|
FM, kg
|
13.25 ± 6.20
|
12.10(10.30-17.15)
|
12.00(9.00-18.00)
|
0.664
|
Percent fat mass, %
|
21.75 ± 8.92
|
24.40(19.50-33.50)
|
19.20(10.60-23.40)
|
0.018
|
LBM, kg
|
44.87 ± 8.34
|
40.30(35.90-41.95)
|
52.20(46.8-54.80)
|
<0.001
|
FFMI, kg/m2
|
16.99± 1.89
|
15.78(14.90-16.41)
|
17.84(16.95-19.33)
|
<0.001
|
TBW, kg
Hemoglobin
|
35.92 ± 6.65
9.41 ± 1.20
|
32.00(28.70-33.55)
9.40(8.65-10.00)
|
41.50(37.60-43.90)
9.90(8.60-10.20)
|
<0.001
0.57
|
Data were presented as mean ± SD (standard deviation) or median (IQR; interquartile range). Asp. Sig. (Asymptotic significance) of difference between female and male (non-parametric, Mann- Whitney U test). Abbreviations: TSFT, triceps skinfold thickness; MAC, mid-arm circumference; MAMC, mid-arm muscle circumference; MAFA, mid-arm fat area; cMAMA, corrected mid-arm muscle area; MAMA, mid-arm muscle area; BMI, body mass index; DBW, dry body weight; LBM, lean body mass; FM, fat mass; FFMI, height –normalized indices of fat-free mass.
Table 2A Correlation coefficients of triceps skinfold thickness (TSFT), mid-arm circumference (MAC), mid-arm muscle circumference (MAMC), mid-arm fat area (MAFA), corrected mid-arm muscle area (cMAMA), mid-arm muscle area (MAMA), body mass index (BMI), gender, percent fat mass (%FM) and height- normalized indices of fat –free mass (FFMI)
|
MAC
|
MAMC
|
cMAMA
|
MAMA
|
TSFT
|
MAFA
|
gender
|
BMI
|
FFMI
|
0.446*
|
0.718***
|
0.653***
|
0.727***
|
-0.246
|
-0.099
|
0.659***
|
0.515**
|
%FM
|
0.498**
|
-0.196
|
-0.110
|
-0.197
|
0.703***
|
0.718***
|
-0.466**
|
0.627***
|
*P< 0.05, **p < 0.01, ***P<0.001, by Pearson correlation. Abbreviations: TSFT, triceps skinfold thickness; MAC, mid-arm circumference; MAMC, mid-arm muscle circumference; MAFA, mid-arm fat area; cMAMA, corrected mid-arm muscle area; MAMA, mid-arm muscle area; BMI, body mass index; %FM, percent fat mass; FFMI, height- normalized indices of fat –free mass.
Table 2B Correlation coefficients of triceps skinfold thickness (TSFT), mid-arm circumference (MAC), mid-arm muscle circumference (MAMC), mid-arm fat area (MAFA), corrected mid-arm muscle area (cMAMA), and mid-arm muscle area (MAMA) with total protein, albumin, blood urea nitrogen, creatinine, cholesterol, and triglyceride (TG)
|
MAC
|
MAMC
|
cMAMA
|
MAMA
|
TSFT
|
MAFA
|
TP
|
0.356*
|
0.243
|
0.275
|
0.248
|
0.126
|
0.199
|
albumin
|
0.506**
|
0.356*
|
0.393*
|
0.378*
|
0.170
|
0.241
|
BUN
|
0.017
|
0.031
|
0.067
|
0.034
|
-0.014
|
-0.021
|
creatinine
|
0.562**
|
0.576**
|
0.560**
|
0.575**
|
0.011
|
0.126
|
cholesterol
|
0.207
|
-0.081
|
-0.082
|
-0.097
|
0.292
|
0.301
|
triglyceride
|
0.292
|
-0.085
|
-0.068
|
-0.089
|
0.384*
|
0.390*
|
*P< 0.05, **p < 0.01, by Pearson correlation. Abbreviations: triceps skinfold thickness (TSFT); MAC, mid-arm circumference; MAMC, mid-arm muscle circumference; MAFA, mid-arm fat area; cMAMA, corrected mid-arm muscle area; MAMA, mid-arm muscle area.
Tables 3A. Hierarchical multiple regression analyses of variables affecting height normalized indices of fat free mass
|
model
|
MAC Model
|
MAMC Model
|
MAMA Model
|
cMAMA Model
|
|
ß
|
R2
change
|
SE
|
ß
|
R2 change
|
SE
|
ß
|
R2 change
|
SE
|
ß
|
R2
change
|
SE
|
Gender
|
0.617***
|
0.434
|
0.440
|
0.429**
|
0.434
|
0.459
|
0.422**
|
0.434
|
0.457
|
0.495***
|
0.434
|
0.419
|
BMI
|
0.506*
|
0.194
|
0.120
|
0.319**
|
0.194
|
0.075
|
0.313*
|
0.194
|
0.074
|
0.319*
|
0.194
|
0.075
|
MAC
|
-0.082
|
0.003
|
0.122
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
MAMC
|
-
|
-
|
-
|
0.357*
|
0.075
|
0.092
|
-
|
-
|
-
|
-
|
-
|
-
|
MAMA
|
-
|
-
|
-
|
-
|
-
|
-
|
0.369*
|
0.080
|
<0.001
|
-
|
-
|
-
|
cMAMA
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
-
|
0.322*
|
0.073
|
<0.001
|
Total R2
|
0.631
|
0.703*
|
0.708*
|
0.701*
|
Abbreviations: BMI, body mass index; MAMC, mid-arm muscle circumference; MAMA, mid-arm muscle area; cMAMA, corrected mid-arm muscle area; MAC, mid-arm circumference; ß, standardized coefficient; SE, standardized error; *p< 0.05; **p< 0.01; ***p<0.001
Tables 3B. Hierarchical multiple regression analyses of variables affecting percent fat mass
|
|
MAC Model
|
TSFT Model
|
MAFA Model
|
|
ß
|
R2 change
|
SE
|
ß
|
R2
change
|
SE
|
ß
|
R2
change
|
SE
|
Gender
|
-0.575***
|
0.217
|
1.854
|
-0.417***
|
0.217
|
1.681
|
-0.448***
|
0.217
|
1.659
|
BMI
|
0.531**
|
0.472
|
0.507
|
0.531***
|
0.472
|
0.308
|
0.482***
|
0.472
|
0.339
|
MAC
|
0.211
|
0.017
|
0.515
|
-
|
-
|
-
|
-
|
-
|
-
|
TSFT
|
-
|
-
|
-
|
0.366**
|
0.096
|
0.103
|
-
|
-
|
-
|
MAFA
|
-
|
-
|
-
|
-
|
-
|
-
|
0.372**
|
0.089
|
0.001
|
Total R2
|
0.706
|
0.785**
|
0.778**
|
Abbreviations: ß, standardized coefficient; SE, standardized error; BMI, body mass index; MAC, mid-arm circumference; TSFT, triceps skin-fold thickness; MAFA, mid-arm fat mass; *p< 0.05; **p< 0.01; ***p<0.001
Table 4. Prediction Equations for Height Normalized indices of Lean Body Mass and Percent Fat Mass
|
equations
|
Predicted equation for MAMC Model
|
6.938+1.598* (1 if male; 0 if female) + 0.210*BMI (kg /m2) +0.245*MAMC (cm)
|
Predicted equation for MAMA Model
|
9.327+1.537* (1 if male; 0 if female) + 0.206*BMI (kg /m2) +0.001*MAMA (cm2)
|
Predicted equation for cMAMA Model
|
9.803+1.843* (1 if male; 0 if female) + 0.210*BMI (kg /m2) +0.001*cMAMA(cm2)
|
Predicted equation for TSF Model
|
-18.718-7.339* (1 if male; 0 if female) + 1.648*BMI (kg /m2) +0.365*TSF (cm)
|
Predicted equation for MAFA Model
|
-15.131-7.880* (1 if male; 0 if female) + 1.495 *BMI (kg /m2) +0.003*MAFA (cm2)
|
Abbreviations: BMI, body mass index; MAMC, mid-arm muscle circumference; MAMA, mid-arm muscle area; cMAMA, corrected mid-arm muscle area; TSFT, triceps skin-fold thickness; MAFA, mid-arm fat mass.
Constants and unstandardized coefficients were used in the equations.