Table 3.

Carotid artery magnetic resonance imaging measures in study participants

Carotid artery variable	Patients with RA, n = 64	Controls, n = 24	Unadjusted differences in RA group from controls		Mean difference adjusted for age and sex		Mean difference adjusted for age, sex and CV risk factorsb
			Mean (95% CI)	P value	B (95% CI)	P value	B (95%)	P value
Mean wall thickness, mm	1.051 (0.125)	1.029 (0.129)	0.022 (− 0.038, 0.082)	0.460	0.002 (− 0.060, 0.064)	0.940	−0.009 (− 0.079, 0.060)	0.790
Minimum wall thickness, mm	0.747 (0.096)	0.718 (0.107)	0.029 (− 0.019, 0.076)	0.230	0.013 (− 0.036, 0.063)	0.591	0.000 (− 0.056, 0.056)	0.990
Maximum wall thickness, mm	1.498 (0.330)	1.530 (0.311)	− 0.031 (− 0.186, 0.123)	0.688	− 0.050 (− 0.217, 0.118)	0.556	− 0.045 (− 0.237, 0.148)c	0.646
Wall volumea, ul	234.528 (45.187) (n = 60)	225.613 (46.751)	8.914 (−13.010, 30.839)	0.421	−5.053 (−26.236, 16.131)	0.636	−5.479 (−28.979, 18.021)	0.644
Luminal volumea, ul	383.408 (116.277) (n = 60)	368.753 (105.625)	14.655 (−39.82, 69.135)	0.594	−0.430 (−55.585, 54.726)	0.988	−8.792 (−71.799, 54.215)	0.782
Wall volume indexeda	0.385(0.046) (n = 60)	0.385 (0.040)	0.001 (− 0.020, 0.022)	0.930	0.001 (−0.023, 0.024)	0.963	0.001 (−0.026, 0.027)	0.952
Wall volume indexed/BSA	0.216 (0.036) (n = 60)	0.221 (0.032)	−0.005 (− 0.021, 0.012)	0.567	− 0.11 (− 0.029, 0.006)	0.201	−0.008 (− 0.028, 0.012)	0.430

CV cardiovascular, BSA body surface area, RA rheumatoid arthritis

^aOf 6 mm length of carotid artery. Carotid wall volume indexed calculated by carotid wall volume/(carotid wall volume + luminal volume)

^bCV risk factors defined as: hypertension (history of hypertension or anti-hypertensive agent), dyslipidaemia (history of dyslipidaemia, on lipid-lowering medication or total cholesterol/high-density lipoprotein cholesterol ratio > 6), ever smoked and family history of premature cardiovascular disease

^cHeteroskedasticity of residuals therefore robust standard errors employed to compensate