Ninety-five participants were enrolled in this study, fifty-seven (60%) were male, and the average age was thirty-four years old. Participants demographical and body composition parameters are shown in Table 1.
Table 1
Participants demographic characteristics
Variables
|
Mean ± SD/Median (percentage/IQR)
|
Body composition indicators
|
Men
|
57(60%)
|
Age
|
34.3 ± 15.12
|
Height(cm)
|
168.1 ± 7.76
|
Weight(kg)
|
74.6 ± 17.29
|
Body mass index (kg/m2)
|
26.3 ± 5.13
|
Waist circumference (cm)
|
87.9 ± 14.64
|
Visceral fat area(cm2)
|
96.7 ± 48.98
|
Liver function indicators
|
TB
|
12.4(8.9)
|
LDH
|
191.0(79.5)
|
ALT
|
24.0(30.0)
|
AST
|
23.5(17.3)
|
ALP
|
78.0(29.0)
|
GGT
|
25.0(34.0)
|
Lipid metabolism indicators
|
TG
|
4.8 ± 1.23
|
TC
|
1.5(1.1)
|
HDL
|
1.3 ± 0.99
|
LDL
|
3.0 ± 0.91
|
The difference of obesity indicators BMI, WC and VFA were analyzed between lipid metabolism variables TG, TC, HDL and LDL normal and unnormal groups. According to medical diagnosis results of TG and TC, there is no significant difference in the comparison of BMI, WC and VFA between normal and unnormal groups. While in HDL and LDL normal groups, VFA were lower than unnormal groups and significant statistics were obtained (P < 0.05). HDL and LDL disorder group with a higher VFA, while there are no significant differences in BMI, WC between normal and unnormal groups for serum HDL and LDL levels. This may indicate VFA has a better predicational ability in the diagnosis of lipid metabolism than BMI and WC (Table 2).
Table 2
Comparison of obesity variables between lipid metabolism indicators
Variables
|
Normal
|
Unnormal
|
p value
|
TG
|
BMI
|
27.2 ± 4.59
|
27.4 ± 4.80
|
0.872
|
WC
|
90.1 ± 14.54
|
90.2 ± 14.24
|
0.973
|
VFA
|
103.5 ± 53.59
|
102.5 ± 41.34
|
0.937
|
TC
|
BMI
|
27.2 ± 4.34
|
26.7 ± 4.57
|
0.648
|
WC
|
88.8 ± 14.88
|
89.0 ± 12.78
|
0.953
|
VFA
|
103.6 ± 50.82
|
89.9 ± 39.51
|
0.212
|
HDL
|
BMI
|
26.9 ± 4.92
|
28.0 ± 3.54
|
0.298
|
WC
|
87.6 ± 15.35
|
93.0 ± 11.17
|
0.104
|
VFA
|
87.3 ± 47.99*
|
115.8 ± 40.49*
|
0.010*
|
LDL
|
BMI
|
26.5 ± 4.37
|
27.8 ± 4.32
|
0.223
|
WC
|
87.0 ± 14.15
|
91.8 ± 12.23
|
0.138
|
VFA
|
90.5 ± 50.05*
|
109.0 ± 40.34*
|
0.049*
|
Note: Mean ± SD. |
* Compared with lipid metabolism disorder group, p < 0.05 means statistical significance. |
The difference of BMI, WC and VFA were analyzed between liver function variables TB, AST, GGT, ALT, LDH and ALP comparison groups, respectively. According to biochemical testing results, VFA was higher in the LDH disorder group than in the normal, and the difference was significant(144.6cm2 > 96.2cm2, p = 0.016). BMI, WC and VFA were manifested positively correlated to ALT and AST. (Table 3).
Table 3
Comparison of obesity variables between liver function indicators
Variables
|
Normal
|
Unnormal
|
p value
|
TB
|
BMI
|
26.4 ± 5.23
|
25.6 ± 4.91
|
0.485
|
WC
|
88.6 ± 14.49
|
85.1 ± 15.35
|
0.329
|
VFA
|
100.6 ± 50.40
|
81.9 ± 41.93
|
0.118
|
LDH
|
BMI
|
26.7 ± 4.94
|
25.5 ± 6.65
|
0.353
|
WC
|
89.2 ± 14.27
|
85.5 ± 17.17
|
0.361
|
VFA
|
96.2 ± 45.05*
|
144.6 ± 50.13*
|
0.016
|
ALT
|
BMI
|
25.7 ± 4.27*
|
29.8 ± 6.08*
|
0.037
|
WC
|
85.6 ± 12.60*
|
98.5 ± 13.43*
|
0.006
|
VFA
|
88.4 ± 42.45*
|
38.8 ± 43.03*
|
0.003
|
AST
|
BMI
|
26.7 ± 3.97*
|
32.1 ± 6.05*
|
0.003
|
WC
|
88.2 ± 13.04*
|
104.1 ± 13.70*
|
0.006
|
VFA
|
95.5 ± 43.67*
|
142.1 ± 53.75*
|
0.017
|
ALP
|
BMI
|
26.3 ± 5.13
|
-
|
-
|
WC
|
87.9 ± 14.64
|
-
|
-
|
VFA
|
96.7 ± 48.98
|
-
|
-
|
GGT
|
BMI
|
25.9 ± 5.01
|
27.5 ± 5.40
|
0.178
|
WC
|
86.4 ± 14.52
|
92.1 ± 14.46
|
0.100
|
VFA
|
94.5 ± 50.65
|
103.2 ± 44.03
|
0.456
|
Note: Mean ± SD. |
*Compared with liver dysfunction group, p < 0.05 means statistical significance. |
The variables BMI, WC and VFA ROC curve were drawn. AUC, the premium cutoff points, sensitivity, and specificity were calculated. VFA presented a distinguished difference in HDL and LDL disorder groups (Fig. 1). The AUC and premium cutoff points for VFA, BMI and WC were showed in Table 4. AUC of VFA was over than 0.7 revealed great ability of related to lipid HDL metabolism (p = 0.004). Based on the ROC cutoff points, chi-square test was conducted between HDL and LDL groups, OR (odds ratio) and 95% CI (95% confidence interval) were calculated. Figures 1 and 2 showed the ROC curves with the value of diagnostic accuracy of lipid metabolism and liver function in the identification of disorder. The curve reveals that VFA (AUC = 0.701, 95% CI 0.577–0.826, p = 0.004) provides a better diagnostic accuracy to distinguish between HDL disorder and normal groups. The optimal cut-off value for VFA was 80.2cm2 with 81.3% sensitivity and 56.8% specificity. For LDH disorder, a cut-off value of VFA 125.3 cm2 shows a sensitivity of 83.3% and specificity of 78.9% (AUC = 0.792, 95% CI 0.595–0.989, p = 0.019). In AST and ALT indicators groups, BMI, WC and VFA were also showed good prompting ability of disorder with significant values (Table 4).
Table 4
AUC of VFA, BMI, WC and premium cutoff points from indicator’s ROC
Variables
|
Area
|
P value
|
95%CI
|
Sensitivity
|
Specificity
|
HDL
|
BMI < 25.7kg/m2
|
0.610
|
0.118
|
0.495–0.759
|
81.3
|
45.9
|
WC < 79.7cm
|
0.627
|
0.070
|
0.475–0.744
|
93.8
|
35.1
|
VFA < 80.2cm2
|
0.701
|
0.004
|
0.577–0.826
|
81.3
|
56.8
|
LDL
|
BMI < 25.7kg/m2
|
0.602
|
0.135
|
0.471–0.732
|
72.7
|
46.3
|
WC < 80.3cm
|
0.593
|
0.171
|
0.464–0.723
|
84.8
|
34.1
|
VFA < 78.6cm2
|
0.629
|
0.058
|
0.500-0.758
|
78.8
|
53.7
|
LDH
|
BMI < 34.3kg/m2
|
0.678
|
0.153
|
0.423–0.934
|
50.0
|
93.0
|
WC < 93.2cm
|
0.709
|
0.094
|
0.496–0.922
|
83.3
|
66.7
|
VFA < 125.3cm2
|
0.792
|
0.019
|
0.595–0.989
|
83.3
|
78.9
|
AST
|
BMI < 32.2kg/m2
|
0.747
|
0.046
|
0.500-0.995
|
66.7
|
93.7
|
WC < 108.5cm
|
0.806
|
0.014
|
0.587-1.000
|
66.7
|
93.7
|
VFA < 121.3cm2
|
0.745
|
0.049
|
0.521–0.968
|
66.7
|
78.1
|
ALT
|
BMI < 26.5kg/m2
|
0.782
|
0.001
|
0.665–0.899
|
85.7
|
63.2
|
WC < 95.3cm
|
0.806
|
0.000
|
0.671–0.941
|
78.6
|
80.7
|
VFA < 130.2cm2
|
0.742
|
0.005
|
0.593–0.892
|
57.1
|
87.7
|
A multivariate analysis was performed to calculate the risk of lipid metabolism disorder and liver dysfunction using the obtained cut-off values (Table 4). The results showed that VFA > 80.2cm2 (OR = 2.81, p = 0.034), VFA > 125.3cm2 (OR = 18.75, P = 0.01) and WC > 95.3cm (OR = 6.55, p = 0.023) were significantly related to HDL disorder, LDH disorder and ALT disorder, respectively (Table 5).
Table 5
BMI, WC and VFA as variables to predict lipid metabolism disorder and liver disfunction logistic regression analysis
Category
|
B
|
P value
|
OR
|
95%CI
|
HDL disorder
|
VFA < 80.2cm2
|
1.03
|
0.034
|
2.81
|
1.08–7.30
|
LDH disorder
|
VFA < 125.3cm2
|
2.93
|
0.01
|
18.75
|
2.00-176.03
|
AST disorder
|
BMI < 32.2kg/m2
|
1.00
|
0.513
|
2.72
|
0.14–54.36
|
WC < 108.5cm
|
1.00
|
0.513
|
2.72
|
0.14–54.36
|
VFA < 121.3cm2
|
0.10
|
0.890
|
1.11
|
0.26–4.71
|
ALT disorder
|
BMI < 26.5kg/m2
|
-1.21
|
0.195
|
0.30
|
0.05–1.86
|
WC < 95.3cm
|
1.88
|
0.023
|
6.55
|
1.29–33.25
|
VFA < 130.2cm2
|
1.35
|
0.097
|
3.86
|
0.78–19.06
|