Established coronary artery disease in systemic sclerosis compared to type 2 diabetic female patients: a cross-sectional study

Introduction: Systemic sclerosis (SSc) is an autoimmune disease characterized by endothelial dysfunction, which is also associated with other disorders, such as atherosclerosis. The direct role of SSc in facilitating cardiovascular events should be clarified. We compared the prevalence of established coronary artery disease (CAD) between SSc and type 2 diabetes, a well-known phenotype associated with high cardiovascular risk. Methods: In this cross-sectional study, we evaluated a cohort of 290 unselected female SSc patients, in comparison with 265 aged-matched female type 2 diabetics. “Established CAD” was defined as previous myocardial infarction, unstable angina or ischemia documented by ECG and troponin elevation, necessity/previous treatment with coronary angioplasty or stenting. Age subgroups < 45 (Q1), 45–54 (Q2), 55–64 (Q3), 65–74 (Q4), and ≥ 75 (Q5) years were considered for SSc and diabetes. Results: CAD prevalence resulted lower in SSc patients than in diabetics (10% (95%CI 6.9–14.1) versus 19.2% (95%CI 14.9–24.4); p = 0.0023). In Q2 patients, CAD never occurred in SSc (95%CI 0–8.4), but in 9.4% of diabetics (95%CI 3.7–20.7, p = 0.0567); in Q3 subjects, CAD was reported in 5.6% (95%CI 1.8–13.8) of SSc, but in 20% (95%CI 12.4–30.5) of diabetics (p = 0.0127). Instead, for Q4 and particularly Q5 patients, CAD prevalence was comparable in SSc and diabetes. Conclusions: The prevalence of established CAD in SSc was lower compared with diabetics. However, in older SSc patients the prevalence of CAD was similar to that observed in diabetics.