Circulating levels of galectin-3 and coronary microvascular perfusion in rheumatoid arthritis patients with suppressed inflammation

Objective Cardiovascular manifestations are the leading cause of mortality in rheumatoid arthritis (RA). Galectin-3, a lectin protein with major role in cellular, inflammatory, and fibrotic processes, has been introduced as a novel cardiac biomarker. We hypothesized that patients with RA present increased levels of galectin-3, and investigated potential associations with arterial stiffness and coronary microvascular dysfunction. Methods This cross-sectional study enrolled RA patients and non-RA individuals without cardiovascular comorbidities. Galectin-3 and high-sensitivity C-reactive protein (hsCRP) were measured with enzyme-linked immunosorbent assay (ELISA) in serum samples. Subendocardial viability ratio (SEVR), an index of microvascular myocardial perfusion, and pulse wave velocity (PWV), the gold-standard measure of vascular stiffness, were estimated with applanation tonometry. Results Cardiovascular risk factors and hsCRP were comparable between patients ( n = 24) and controls ( n = 24). However, galectin-3 was increased [6.9 (6.7) vs 4.6 (4.7)] ng/dl, p = 0.015], and coronary microvascular perfusion was decreased (142.6 ± 22.8 vs 159.7 ± 23.2%, p = 0.028) in RA patients compared to controls, whereas PWV did not significantly differ. Galectin-3 correlated with both PWV and SEVR in univariate analysis. However, after adjustment for cardiovascular risk factors and subclinical inflammation, these associations were rendered non-significant. Conclusion Galectin-3 appears increased in RA, even among patients with suppressed inflammation in the absence of cardiovascular comorbidities. The observed association of galectin-3 with coronary microvascular perfusion in our study was non-significant after adjustment for cardiovascular risk factors and inflammation. The potential role of galectin-3 as a cardiac biomarker in RA warrants further investigation. Key Points • Galectin-3 has emerged as a novel cardiac biomarker but remains understudied in RA. • Patients with RA present elevated levels of galectin-3 and impaired coronary microvascular perfusion compared to non-RA individuals. • These differences were observed in patients with suppressed inflammation, even in the absence of CVD. • The association of galectin-3 with coronary microvascular impairment in RA warrants further investigation.