Objective: Accelerated atherosclerosis in inflammatory rheumatic diseases such as ankylosing spondylitis (AS) stands out among the leading causes of morbidity and mortality. We assessed the correlation between subclinical carotid atherosclerosis and its related clinical parameters in AS patients.
Methods: Twenty-eight patients (23 males, 5 females) with AS and 27 sex- and age-matched controls were consecutively recruited to this study. We estimated the carotid intima-media thickness (IMT) and parameters related to arterial elastic properties, including the distensibility coefficient (DC), stiffness index (beta), and incremental elastic modulus (E(inc)) using high-resolution ultrasonography. Serum levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1) were measured using enzyme-linked immunosorbent assay (ELISA).
Results: Carotid IMT values and arterial elastic parameters in AS patients showed no statistical significance compared to those of controls (0.57+/-0.07 vs 0.55+/-0.05, p=0.387 for IMT, 28.45+/-9.23 vs 31.93+/-9.52, p=0.175 for DC, 2.32+/-0.18 vs 2.29+/-0.15, p=0.559 for stiffness index (beta), and 0.14+/-0.05 vs 0.12+/-0.03, p=0.116 for E(inc)). The serum level of IL-6 in AS patients was significantly different compared with controls (p=0.001), but not in serum levels of TNF-alpha and MCP-1 (p=0.162, p=0.087, respectively). Carotid IMT and all arterial elastic parameters calculated in this study were not found to be associated with serum levels of TNF-alpha, IL-6, and MCP-1.
Conclusion: This cross-sectional study showed that carotid IMT and parameters related with arterial elastic properties in young AS patients without clinically evident cardiovascular risk factors were not different from those of sex- and age-matched healthy controls. Serum levels of TNF-alpha, IL-6, and MCP-1 did not reflect the degree of carotid subclinical atherosclerosis. However, these findings should be confirmed further in a larger population.