Variables associated with subclinical atherosclerosis in a cohort of rheumatoid arthritis patients: Sex-specific associations and differential effects of disease activity and age

Objective: To advance the study of variables associated with subclinical atherosclerosis in rheumatoid arthritis (RA) with special consideration for the degree of disease activity, age and gender. Methods: The carotid intima-media thickness (cIMT) and the presence of carotid atherosclerotic plaques along with clinical and biochemical characteristics were determined in 214 RA patients. Results: Adjusted analysis reveals that men had a 0.059 mm significantly increased cIMT compared with women (p = 0.001; R2 = 3.8%) and that age was associated with cIMT (β = 0.0048 mm; p = 0.0001; R2 = 16%). Interestingly, we observed a significant interaction between gender and age. Thus, the effect of age on cIMT was significantly increased (12%) in men compared with women (p-value for interaction term = 0.041). Moreover, adjusted multivariable linear regression analysis revealed that disease activity score (DAS28) was significantly associated with cIMT in women (β = 0.021; p = 0.018: R2 = 0.03) but not men. In particular, women with high disease activity had a 0.079 mm increased cIMT compared with women in remission (p = 0.026). In addition, men in remission had a 0.134 mm increased cIMT compared with women in remission (p = 0.003; R2 = 8.7%). Active patients did not exhibit differences in cIMT values. Furthermore, 43% of patients presented carotid plaques. The variables independently associated with carotid plaques were age, smoking, health assessment questionnaire, erythrocyte sedimentation rate and rheumatoid factor (p