Serum prolidase activity and oxidative–antioxidative status in patients with developmental dysplasia of the hip and its relationship with radiographic severity

Figures & data

Table 1 Demographic characteristics of the DDH and control groups

	Patients* (n= 93)	Controls* (n = 82)	P value
Age (months)	17.72 ± 6.54	19.02 ± 6.69	0.195
Affected side (L/R)	65/28
Gender (female/male)	71/22	59/23	0.624
Prolidase (U/l)	584.26 ± 28.48	531.66 ± 19.96	<0.001
LOOH (µmol/l)	6.68 ± 2.21	5.65 ± 1.73	<0.001
TOS (µmol H2O2 equiv./l)	11.66 ± 3.63	10.11 ± 3.74	0.006
OSI (arbitrary unit)	1.19 ± 0.47	0.93 ± 0.41	<0.001
Total –SH (mmol/l)	0.30 ± 0.47	0.31 ± 0.4	0.007
TAC (mmol Trolox equiv./l)	1.01 ± 0.15	1.12 ± 0.25	<0.001

*Measurements are given as the mean ± SD.

LOOH, lipid hydroperoxide; TOS, total oxidant status; OSI, oxidative stress index; –SH, free sulfhydryl groups; TAC, total antioxidant capacity.

Figure 1 Graph demonstrating that the lowest and highest mean serum paraoxonase activities were detected in patients with grade 1 and grade 4 DDH, respectively (ANOVA, P < 0.001)

Table 2 Demographic characteristics of the DDH according to Tonnis grade

Tonnis Grade	I (n = 21)	II (n = 24)	III (n = 22)	IV (n = 26)	P value
Age (months)	16.85 ± 6.84	18.08 ± 6.53	17.22 ± 6.44	18.50 ± 6.67	0.823
Gender (female/male)	15/6	19/5	17/5	20/6	0.739
Prolidase (U/l)	552.96 ± 17.11	574.72 ± 15.75	590.72 ± 20.47	612.91 ± 19.25	<0.001
LOOH (µmol/l)	5.59 ± 1.85	6.16 ± 1.81	7.19 ± 2.29	8.24 ± 1.98	<0.001
TOS (µmol H2O2 equiv./l)	8.86 ± 1.51	10.12 ± 2.74	12.63 ± 4.21	14.51 ± 2.61	<0.001
OSI (arbitrary unit)	0.78 ± 0.15	1.01 ± 0.28	1.35 ± 0.55	1.58 ± 0.36	<0.001
Total –SH (mmol/l)	0.32 ± 0.02	0.31 ± 0.43	0.29 ± 0.04	0.27 ± 0.05	<0.001
TAC (mmol Trolox equiv./l)	1.14 ± 0.14	1.01 ± 0.13	0.99 ± 0.12	0.96 ± 0.15	<0.001

LOOH, lipid hydroperoxide; TOS, total oxidant status; OSI, oxidative stress index; –SH, free sulfhydryl groups; TAC, total antioxidant capacity.

Figure 2 The correlation of LOOH with prolidase activity

Figure 3 The correlation of TOS with prolidase activity

Figure 4 The correlation of OSI with prolidase activity

Table 3 Relationship between serum prolidase activity and clinical characteristics and laboratory parameters

	Pearson's correlation coefficient	P value	β-Regression coefficient*	P value
Tonnis grade of DDH	0.775	<0.001	0.711	<0.001
LOOH (µmol/l)	0.377	<0.001
TOS (µmol H2O2 equiv./l)	0.462	<0.001	0.675	0.040
OSI (arbitrary units)	0.568	<0.001	0.789	0.042
Total –SH (mmol/l)	–0.467	<0.001
TAC (mmol Trolox equiv./l)	–0.408	<0.001

*From multiple linear regression.

LOOH, lipid hydroperoxide; TOS, total oxidant status; OSI, oxidative stress index; –SH, free sulfhydryl groups; TAC, total antioxidant capacity.