Table 4

Biomarker levels in each subgroups according to both the radiographic classification and knee pain

Radiographic OA

Pain

Mean

SE

95% CI of the mean

P-value

95% CI for difference

Lower

Upper


sC2C

K/L 1

-

5.49

0.04

5.40

5.57

0.02*

-0.19 to -0.04

Ln (pmol/ml)

+

5.75

0.07

5.61

5.91

K/L 2

-

5.43

0.07

5.29

5.57

1.00

-0.36 to 0.35

+

5.44

0.11

5.21

5.66

sCPII

K/L 1

-

7.38

0.07

7.24

7.52

0.01*

-0.83 to -0.10

Ln (ng/ml)

+

7.84

0.11

7.62

8.07

K/L 2

-

7.05

0.11

6.83

7.28

1.00

-0.44 to 0.71

+

6.92

0.18

6.56

7.28

uCTX-II/Cr

K/L 1

-

5.04

0.14

4.76

5.32

0.07

-1.48 to 0.03

Ln (ng/╬╝mol creatinine)

+

5.77

0.22

5.32

6.22

K/L 2

-

5.38

0.23

4.92

5.83

<0.05*

-2.36 to -0.05

+

6.56

0.36

5.82

7.29

sC2C

K/L 1

-

0.15

0.03

0.10

0.20

1.00

-1.12 to 0.17

/sCPII

+

0.12

0.04

0.04

0.21

K/L 2

-

0.27

0.04

0.19

0.36

1.00

-0.17 to 0.26

+

0.23

0.07

0.09

0.37

uCTX-II/sCPII

K/L 1

-

0.09

0.06

-0.03

0.22

1.00

-0.39 to 0.29

+

0.14

0.10

-0.06

0.35

K/L 2

-

0.42

0.10

0.21

0.63

<0.05*

-1.07 to 0

+

0.95

0.17

0.62

1.29

uNTX/Cr

K/L 1

-

3.71

0.11

3.48

3.93

1.00

-0.89 to 0.33

Ln (ng/ml creatinine)

+

3.99

0.18

3.62

4.35

K/L 2

-

3.33

0.18

2.96

3.70

0.73

-1.49 to 0.41

+

3.87

0.29

3.27

4.47

sHA

K/L 1

-

2.77

0.13

2.51

3.03

0.06

-1.40 to 0.01

Ln (pmol/ml)

+

3.46

0.21

3.04

3.89

K/L 2

-

3.66

0.21

3.24

4.09

1.00

-1.42 to 0.78

+

3.98

0.34

3.29

4.67


All analyses were adjusted for age, sex and body mass index. The urinary biomarkers were corrected for creatinine. *P-values less than or equal to 0.05 are statistically significant.

95% CI, 95% confidence interval; C2C, cartilage collagen type II cleavage; CPII, cartilage type II collagen carboxy propeptide; CTX-II, type II collagen C-telopeptide; HA, hyaluronic acid; K/L, Kellgren-Lawrence grade; Ln, natural log; NTx, N-terminal crosslinking telopeptide of type I collagen; s, serum; SE, standard error of the mean; u, urine.

Ishijima et al. Arthritis Research & Therapy 2011 13:R22   doi:10.1186/ar3246

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