Background Rheumatoid arthritis (RA) is recognized as an independent cardiovascular risk factor. The ongoing inflammatory state in RA is believed to be the main cause of this increased cardiovascular risk since inflammation is a key contributor to atherosclerosis. Carotid intima media thickness (cIMT) is a surrogate marker for (subclinical) atherosclerosis.
Objectives To identify clinical parameters related to cIMT in patients with RA.
Methods RA patients <70 years of age without cardiovascular disease (AMI, PTCA, CABG, CVA, TIA, severe claudicatio, PTA and/or amputation due to peripheral arterial disease) and/or diabetes mellitus were included. Patients underwent a standard physical examination including the DAS28. Standard laboratory measurements included a fasting lipid profile. cIMT was measured semi-automatically by ultrasound and skin autofluorescence (SAF) was measured using the AGE Reader®. Patients were grouped into tertiles of cIMT. Differences in clinical parameters between the tertiles were tested with ANOVA or chi square. Those parameters with p-ANOVA <0.05 were used in a multivariable linear regression analysis (backward, enter) to identify factors related to cIMT in RA.
Results A total of 310 patients were included with a mean (±SD) age of 53.3±11.3 years and a median (IQR) RA disease duration of 7.00 (2.00-14.00) years. The median (IQR) DAS28 was 2.2 (1.7-3.0) reflecting low RA disease activity. 212 (68%) patients were female. The mean cIMT was 0.569±0.122 mm. cIMT showed a positive trend in the univariate analyses with RA disease duration, waist circumference, glucose, LDL-C, apolipoprotein B, systolic blood pressure (BP), body mass index, HbA1c, homocystein and SAF. No association between cIMT and RA disease characteristics (i.e. RF, anti-CCP, erosive disease and DAS28) was found. Multiple linear regression analysis without age as a covariate showed a positive association of cIMT with systolic BP (B 0.011 95%CI 0.002-0.19; p=0.02), glucose (B 0.231 95%CI -0.032-0.494.; p=0.09) and SAF (B 0.302 95% CI 0.001.-0.602.; p=0.049) (adjusted R2= 0.023). When age was included only age was significantly associated with cIMT (B 0.046 95% CI 0.032-0.060; (p<0.001) (adjusted R2=0.450). However, there was a tendency for a contributing effect of systolic BP (B 0.006 95%CI -0.001-0.013; p=0.099).
Conclusions SAF, systolic BP and glucose were associated with cIMT in RA patients. However, age was the strongest predictor for cIMT in RA, which diminished the association of all other parameters including the classical cardiovascular risk factors, SAF and RA disease duration. In view of the strong effect of age on cIMT, the value of a single measurement of cIMT in RA patients seems limited.
Disclosure of Interest None Declared