Table 4

Results of Analyses of covariance with factor RA - group - status and covariate muscle cross - sectional area (CSA)

Bone

Site

Parameter

Difference between intercepts (P-value)

Difference between slopes (P-value)

Slope of RA group (P-value)


Radius

4%

BMC (g/cm)

0.01

(0.610)

- 0.01

(0.045)

0.04

(0.000)

Total CSA (mm2)

- 10.64

(0.190)

- 2.10

(0.319)

7.62

(0.000)

Total BMD (mg/cm3)

15.94

(0.099)

- 1.76

(0.483)

4.16

(0.035)

Trab. BMD (mg/cm3)

28.50

(0.000)

- 3.61

(0.052)

5.29

(0.000)

66%

BMC (g/cm)

0.05

(0.050)

- 0.01

(0.154)

0.03

(0.000)

Total CSA (mm2)

- 10.82

(0.003)

- 1.54

(0.108)

3.84

(0.000)

Cort. CSA (mm2)

5.57

(0.023)

- 0.69

(0.281)

2.70

(0.000)

Cort. BMD (mg/cm3)

42.58

(0.000)

0.55

(0.869)

1.07

(0.686)

Cort. Thickness (mm)

0.29

(0.001)

- 0.01

(0.657)

0.05

(0.004)

Tibia

4%

BMC (g/cm)

0.08

(0.267)

- 0.02

(0.003)

0.04

(0.000)

Total CSA (mm2)

- 53.01

(0.031)

- 5.18

(0.017)

7.80

(0.000)

Total BMD (mg/cm3)

22.13

(0.008)

- 0.52

(0.471)

1.66

(0.005)

Trab. BMD (mg/cm3)

21.71

(0.003)

- 1.68

(0.008)

2.15

(0.000)

66%

BMC (g/cm)

0.02

(0.742)

- 0.01

(0.024)

0.04

(0.000)

Total CSA (mm2)

- 17.41

(0.178)

- 0.91

(0.424)

3.13

(0.001)

Cort. CSA (mm2)

2.75

(0.619)

- 1.38

(0.005)

2.98

(0.000)

Cort. BMD (mg/cm3)

11.42

(0.169)

0.05

(0.944)

0.38

(0.518)

Cort. Thickness (mm)

1.14

(0.171)

- 0.02

(0.038)

0.03

(0.000)

MCP3

4%

BMC (mg/cm)

1.40

(0.266)

- 0.35

(0.287)

1.41

(0.000)

Total CSA (mm2)

- 2.74

(0.299)

- 0.42

(0.543)

1.71

(0.002)

Total BMD (mg/cm3)

21.60

(0.014)

- 3.36

(0.138)

7.52

(0.000)

Trab. BMD (mg/cm3)

25.98

(0.008)

- 4.28

(0.092)

8.64

(0.000)

30%

BMC (mg/cm)

1.67

(0.194)

- 0.60

(0.074)

1.47

(0.000)

Total CSA (mm2)

- 7.33

(0.000)

- 0.86

(0.092)

2.08

(0.000)

Cort. CSA (mm2)

1.76

(0.056)

- 0.49

(0.039)

1.13

(0.000)

Cort. BMD (mg/cm3)

43.98

(0.001)

- 1.39

(0.667)

2.61

(0.300)

Cort. Thickness (mm)

0.16

(0.001)

- 0.01

(0.419)

0.03

(0.014)

50%

BMC (mg/cm)

1.45

(0.229)

- 0.43

(0.168)

1.58

(0.000)

Total CSA (mm2)

- 4.40

(0.000)

- 0.44

(0.113)

1.18

(0.000)

Cort. CSA (mm2)

1.60

(0.073)

- 0.38

(0.099)

1.25

(0.000)

Cort. BMD (mg/cm3)

32.25

(0.002)

- 1.97

(0.452)

4.51

(0.029)

Cort. Thickness (mm)

0.18

(0.002)

- 0.01

(0.588)

0.04

(0.000)

relative cortical area

0.07

(0.000)

- 0.00

(0.617)

0.01

(0.017)


For bone parameters of the radius and metacarpal bone muscle CSA of the forearm (cm2) was used, and for the tibia muscle CSA at the lower leg (cm2) was used. Bold P-values indicate significant coefficients. P-values are rounded to three decimal places, values of 0.000 are equivalent to P < 0.0005. BMC stands for bone mineral content per mm of slice thickness, BMD for volumetric bone mineral density, trab for trabecular and cort for cortical.

Aeberli et al. Arthritis Research & Therapy 2010 12:R119   doi:10.1186/ar3056

Open Data