Factors correlating with acoustic radiation force impulse elastography in chronic hepatitis C

Table 1 Characteristics of 108 patients with chronic hepatitis C virus infection

	All patients (n = 108)	F0 (n = 14)	P values of Mann-Whitney U test between F0 and F1	F1 (n = 17)	P values of Mann-Whitney U test between F0-1 and F2	F2 (n = 32)	P values of Mann-Whitney U test between F2 and F3	F3 (n = 31)	P values of Mann-Whitney U test between F3 and F4	F4 (n = 14)
Age (yr)1	59.5 (49.0-66.0)	48.0 (41.0-60.0)	NS	51.0 (41.8-65.5)	NS	61.5 (51.5-66.5)	NS	61.0 (52.0-67.0)	NS	60.5 (54.0-66.0)
Gender (female/male)2	52/56	8/6	NS	8/9	NS	15/17	NS	13/18	NS	8/6
BMI	22.5 (20.5-24.6)	22.0 (20.0-23.2)	NS	23.5 (19.8-25.4)	NS	23.0 (20.7-24.4)	NS	23.2 (21.1-26.1)	NS	21.9 (19.0-23.4)
Fibrosis stage (F0/F1/F2/F3/F4)	14/17/32/31/14	-		-		-		-		-
Inflammatory grade (A0/A1/A2/A3)	12/32/53/11	9/5/0/0	0.0261	2/15/0/0	0.0001	1/9/22/0	0.0060	0/2/22/7	NS	0/1/9/4
Steatosis grade (S0/S1/S/2/S3)	42/42/14/10	8/5/0/1	NS	7/9/0/1	NS	10/11/6/5	NS	9/14/5/3	NS	8/3/3/0
AST (IU/L)1	44.0 (31.5-82.0)	28.5 (24.0-38.0)	NS	36.0 (23.0-41.3)	0.0033	48.5 (36.5-101.5)	NS	48.0 (42.5-85.3)	NS	65.5 (37.0-88.0)
ALT (IU/L)1	55.0 (35.0-91.5)	37.5 (22.0-59.0)	NS	39.0 (24.8-52.0)	0.0095	65.0 (41.0-153.0)	NS	70.0 (41.3-109.0)	NS	64.0 (36.0-91.0)
γ-GTP (IU/L)1	33.0 (23.5-75.0)	23.0 (14.0-27.0)	0.0802	28.0 (19.5-71.3)	NS	39.5 (24.5-89.5)	NS	41.0 (28.0-96.8)	0.0329	30.5 (27.0-38.0)
Platelet count (× 104/μL)1	14.3 (11.3-17.6)	14.6 (11.7-20.2)	NS	18.2 (16.6-21.2)	0.0107	16.1 (14.0-17.4)	0.0080	12.2 (11.3-14.3)	0.0078	10.1 (7.1-11.6)
Prothrombin time (INR)1	1.00 (0.96-1.06)	0.95 (0.90-0.99)	NS	0.96 (0.93-1.02)	NS	1.00 (0.95-1.03)	0.0144	1.03 (1.00-1.08)	0.0229	1.10 (1.03-1.12)
Albumin (g/dL)1	4.2 (4.0-4.5)	4.4 (4.1-4.6)	NS	4.4 (4.2-4.5)	NS	4.3 (4.0-4.5)	0.0524	4.1 (3.8-4.3)	NS	4.0 (3.8-4.2)
Total cholesterol (mg/dL)1	170 (150-188)	193 (177-207)	0.0619	169 (155-193)	NS	172 (156-189)	0.0615	159 (141-177)	NS	160 (144-183)
γ-globulin (g/dL)1	1.51 (1.33-1.79)	1.28 (1.14-1.40)	0.0262	1.40 (1.28-1.70)	NS	1.44 (1.34-1.64)	0.0067	1.63 (1.51-2.11)	NS	1.66 (1.43-1.97)
Hyaluronic acid (ng/mL)1	89 (49-206)	39 (30-64)	NS	49 (26-77)	0.0041	89 (66-185)	0.0601	184 (82-245)	0.0291	232 (191-338)
HCV genotype (1/2)	81/26	10/4	NS	12/5	NS	22/9	NS	5/26	NS	11/3
HCV RNA (logIU/mL)1	6.6 (5.8-7.0)	6.5 (6.0-6.9)	NS	6.6 (5.4-7.0)	NS	6.6 (5.8-7.1)	NS	6.7 (5.9-7.1)	NS	6.6 (6.3-6.8)
Fibrosis area (%)1	2.63% (1.35-4.95)	0.85% (0.41-1.04)	0.0111	1.37% (0.73-1.85)	0.0022	2.20% (1.62-2.74)	< 0.0001	4.83% (4.03-6.24)	< 0.0001	8.87% (8.04-10.52)
Velocity of shear wave (m/s)1	1.38 (1.19-1.71)	1.2 (1.0-1.3)	NS	1.1 (1.0 -1.2)	0.0010	1.3 (1.2-1.6)	0.0014	1.6 (1.5-1.8)	0.0008	2.1 (1.9-2.2)

¹Data are shown as median (interquartile range);

²Difference of frequency of gender was assessed by χ² test. AST: Aspartate aminotransferase; ALT: Alanine aminotransferase; γ-GTP: γ-glutamyltranspeptidase.

Table 2 Optimal cutoff value of velocity of shear wave for each fibrosis stage was determined at maximum sum of sensitivity and specificity

	F≥1	F≥2	F≥3	F4
Cutoff value (m/s)	1.28	1.28	1.44	1.73
Positive predictive value	97.0%	94.0%	78.4%	48.0%
Negative predictive value	29.3%	65.9%	91.2%	97.6%
Sensitivity	69.1%	81.8%	88.9%	85.7%
Specificity	85.7%	87.1%	82.5%	86.2%
Positive likelihood ratio	4.8	6.3	5.1	6.2
Diagnostic accuracy	71.3%	83.3%	85.2%	86.1%
AUROC	0.810	0.909	0.869	0.885
Standard error of AUROC	0.046	0.027	0.036	0.058

AUROC: Area under receiver operating characteristic curve

Table 3 Optimal cutoff value of fibrosis area for each fibrosis stage was determined at maximum sum of sensitivity and specificity

	F≥1	F≥2	F≥3	F4
Cutoff value	1.17%	1.8%	3.71%	7.32%
Positive predictive value	97.7%	94.3%	93.0%	92.3%
Negative predictive value	60.0%	71.1%	92.3%	97.9%
Sensitivity	91.5%	85.7%	88.9%	85.7%
Specificity	85.7%	87.1%	95.2%	98.9%
Positive likelihood ratio	6.4	6.6	18.7	80.6
Diagnostic accuracy	90.7%	86.1%	92.6%	97.20%
AUROC	0.935	0.927	0.963	0.962
Standard error of AUROC	0.025	0.024	0.018	0.023

AUROC: Area under receiver operating characteristic curve

Table 4 Factors correlating with velocity of shear wave in 108 patients with chronic hepatitis C virus infection

	All patients (n = 108)				Patients with F0 or F1 (n = 31)				Patients with F2 (n = 32)				Patients with F3 or F4 (n = 45)
	Spearman's rank correlation test		Multiple regression analysis		Spearman's rank correlation test		Multiple regression analysis		Spearman's rank correlation test		Multiple regression analysis		Spearman's rank correlation test		Multiple regression analysis
	ρ	P value	β	P value	ρ	P value	β	P value	ρ	P value	β	P value	ρ	P value	β	P value
Age (yr)		NS				NS				NS				NS
Gender (female/male)1		NS				NS				NS				NS
BMI		NS			-0.608	0.0003	-0.033	0.0001		NS				NS
Fibrosis stage	0.732	< 0.0001	0.187	0.0001		NS							0.505	0.0004	0.292	0.0044
Inflammatory grade	0.612	< 0.0001		NS		NS				NS				NS
Steatosis grade		NS				NS				NS				NS
AST (IU/L)	0.430	< 0.0001		NS		NS				NS				NS
ALT (IU/L)	0.318	0.0008		NS	0.343	0.0593		NS		NS				NS
γ-GTP (IU/L)	0.407	< 0.0001		NS	0.340	0.0614		NS	0.544	0.0013	0.005	0.0012		NS
Platelet count (× 104/μL)	-0.441	< 0.0001		NS		NS				NS			-0.425	0.0036		NS
Prothrombin time (INR)	0.344	0.0003		NS		NS				NS			0.390	0.0080		NS
Albumin (g/dL)	-0.347	0.0002		NS		NS				NS			-0.459	0.0015		NS
Total cholesterol (mg/mL)	-0.337	0.0004		NS		NS				NS				NS
γ-globulin (g/dL)	0.252	0.0087		NS		NS			-0.344	0.0581		NS		NS
Hyaluronic acid (ng/mL)	0.576	< 0.0001	8.00E-4	0.0039		NS				NS			0.519	0.0003	0.001	0.0025
HCV genotype (1/2)1		0.0728		NS		NS				NS				NS
HCV RNA (logIU/mL)		NS				NS				NS				NS
Fibrosis area (%)	0.656	< 0.0001		NS		NS				NS			0.296	0.0481		NS
R			0.707				0.645				0.546				0.634
Adjusted R			0.490				0.396				0.275				0.373
F			51.800				20.700				12.700				14.100
P value			< 0.0001				0.0001				0.0012				< 0.0001

¹Difference of frequency of gender or genotype was assessed by Mann-Whitney U test. AST: Aspartate aminotransferase; ALT: Alanine aminotransferase; γ-GTP: γ-glutamyltranspeptidase.