Background Rheumatoid arthritis (RA) is a chronic inflammatory disease which causes juxta-articular and generalized bone loss. Several studies revealed that bone mineral density (BMD) is associated with atherosclerosis.
Objectives In the present study, we investigated the association between BMD and RA disease activity and the carotid atherosclerosis in RA patients based Kyungpook National University Hospital Atherosclerosis Risk in Rheumatoid Arthritis (KARRA) cohort study.
Methods A total of 323 patients with RA, who performed dual-photon x-ray absorptiometry and carotid ultrasound, were included. We assessed RA disease activity, risk factors for atherosclerosis including hypertension, diabetes mellitus and dyslipidemia, presence of carotid plaque, carotid intima-media thickness (IMT), and BMD. BMD was measured at the lumbar spine (L-spine, L1-L4), femur neck (total femur neck) and distal forearm (total radius), and low BMD was defined as a T score of -1.0 or less.
Results The BMD in the L-spine, femur, and radius was significantly lower in patients with carotid plaques (n=152), compared to patients without plaques (n=171) (1.014 g/cm2 ± 0.21 vs. 1.066 g/cm2 ± 0.18, p=0.016 for L-spine; 0.816 g/cm2 ± 0.16 vs. 0.863 g/cm2 ± 0.13, p<0.001 for femur; 0.542 g/cm2 ± 0.13 vs. 0.603 g/cm2 ± 0.12, p<0.001 for radius). The frequency of low BMD in these areas was also higher in patients with carotid plaques, compared to patients without plaques (52.7% vs. 47.5%, p=0.045 for L-spine; 56.0% vs. 44.0%, p=0.001 for femur; 60.6% vs. 39.4%, p<0.001 for radius). Carotid IMT showed a significant difference between patients with low BMD and those with normal BMD (0.84 mm ± 0.14 vs. 0.80 mm ± 0.19, p=0.025 for L-spine; 0.83 mm ± 0.15 vs. 0.80 mm ± 0.18, p=0.045 for femur; 0.85 mm ± 0.15 vs. 0.77 mm ± 0.18, p <0.001 for radius). In subgroup analysis, patients with the highest IMT quartile had a significantly lower BMD in all the regions than those with the lowest IMT quartile (61.2% vs. 37.7%, p=0.004 for L-spine; 59.5% vs. 35.1%, p=0.003 for femur; and 71.4% vs. 28.6%, p<0.001 for radius). Multivariate logistic regression analysis demonstrated that BMD at radius (OR 4.995, 95% CI [1.067–10.276], p<0.001), DAS28-ESR (OR 1.906, 95% CI [1.042–3.046], p=0.036), and dyslipidemia (OR 2.334, 95% CI [1.164–3.156], p=0.02) were risk factors for presence of carotid plaques.
Conclusions The present study showed that carotid atherosclerosis was influenced by both disease activity and impaired bone health.
Im CH et al. Inflammatory burden interacts with conventional cardiovascular risk factors for carotid plaque formation in rheumatoid arthritis. Rheumatology (Oxford). 2015 May;54(5):808–15.
Disclosure of Interest None declared