Table 3.
Assessment of possible effect modifiers on the relation of BMI on CRP in the whole population (428 patients), and on the relation of BMI on ASDAS-CRP in axSpA patients (168 patients) by linear regression modelling
| CRP | ||||
|---|---|---|---|---|
| n=428 (whole population) | β | SE | 95% CI | p Value |
| BMI | 1.14 | 1.30 | −1.41 to 3.70 | 0.38 |
| Age | 0.78 | 2.52 | −4.16 to 5.73 | 0.76 |
| BMI x age | −1.02 | 1.72 | −4.41 to 2.36 | 0.55 |
| BMI | −6.12 | 2.86 | −11.74 to −0.50 | 0.03 |
| Gender | −5.49 | 2.50 | −10.40 to −0.58 | 0.03 |
| BMI x gender | 4.01 | 1.68 | 0.70 to 7.32 | 0.02 |
|
ASDAS-CRP | ||||
| n=168 (axSpA population) | β | SE | 95% CI | p Value |
| BMI | 0.31 | 0.22 | −0.12 to 0.74 | 0.16 |
| Age | 0.15 | 0.42 | −0.69 to 0.98 | 0.73 |
| BMI x age | −0.17 | 0.31 | −0.77 to 0.43 | 0.58 |
| BMI | 0.29 | 0.48 | −0.65 to 1.23 | 0.54 |
| Gender | 0.25 | 0.42 | −0.57 to 1.07 | 0.54 |
| BMI x gender | −0.05 | 0.30 | −0.64 to 0.55 | 0.88 |
p Value in bold: with statistical significance.
x=interaction term.
ASDAS, Ankylosing Spondylitis Disease Activity Score; axSpA, axial spondyloarthritis; BMI, body mass index; CRP, C reactive protein; β, unstandardised β coefficient.