*4.1. Study Population*

In this prospective study, we enrolled 93 patients who met the 2010 revised criteria of the American College of Rheumatology for RA [39] and who had an active disease status. Disease activity was assessed by using the 28-joint disease activity score (DAS28) [40], and active status was defined as DAS28 ≥ 3.2. Each patient had previously received corticosteroids, nonsteroidal anti-inflammatory drugs, and at least one conventional synthetic disease-modifying anti-rheumatic drug (csDMARD). Patients with a recent history (i.e., within one year before enrollment) of coronary artery disease or ischemic stroke were excluded. Follow-up for the emergence of CVD, which included acute myocardial infarction and ischemic stroke, was done for at least two years. The healthy control (HC) group comprised 41 sex- and age-matched healthy volunteers with no rheumatic disease. The Institutional Review Board of our hospital approved this study (CMUH107-REC2-038, approval date 19 March 2018), and each participant's written consent was obtained according to the Declaration of Helsinki.
