Elevated Th17 cells are associated with cardiovascular complications in ankylosing spondylitis

Patients with ankylosing spondylitis (AS) carry an increased burden of cardiovascular diseases (CVD), but features denoting the development of CVD in AS are unclear. This study aimed to evaluate the percentage and absolute number of lymphocytes and CD4+T cells in AS patients complicated with CVD (AS-CVD) and determine whether circulating T helper 17 (Th17) cells are associated with the development of CVD in AS.

A total of 117 AS patients (46 had CVD and 71 had no CVD) were enrolled in this retrospective study. The percentage and absolute number of lymphocytes and CD4+T cells were determined by flow cytometry. Associations between CVD and clinical markers were analysed using logistic regression.

The ratio of Th17/Treg cells (0.30 vs 0.19, P = 0.014) and the absolute number of Th17 cells (7.27 cells/μL vs 4.34 cells/μL, P < 0.001) was significantly elevated in AS-CVD group compared with AS-no-CVD group. Multivariate logistic regression revealed that elevated Th17 cells (OR = 1.20, P = 0.016) were associated with CVD complications in AS. Receiver operating characteristic (ROC) curves showed a contribution of Th17 cell for distinguishing AS patients with CVD, with the areas under the ROC curve (AUCs) of 0.729 (95% CI: 0.632, 0.825, P < 0.001).

Our findings provide evidence for the association between Th17 cells and increased cardiovascular risk in AS. Th17 cells may contribute to accelerated atherogenesis and increased cardiovascular burden in AS and be valuable for early assessment and management of AS-CVD.