Serum fractalkine levels and their association with cardiovascular parameters in patients with overt hyperthyroidism

Aims: Hyperthyroidism is a common endocrine disorder with significant cardiovascular (CV) implications.Emerging evidence links fractalkine to both heart failure (HF) and atherosclerosis.We aimed to compare serum fractalkine levels between patients with hyperthyroidism and healthy controls and to investigate its potential association with CV risk markers.Methods: This case-control study included treatment-naive adults with overt hyperthyroidism and age-and sex-matched healthy controls with normal thyroid function tests.Participants with cardiovascular disease or major systemic disorders were excluded.All participants underwent physical examination, hormonal profiling, serum fractalkine measurement, electrocardiography, and echocardiographic assessment using both conventional and tissue Doppler techniques to evaluate left and right ventricular function.Results: The study included 41 treatment-naive patients with overt hyperthyroidism (mean age: 45±12.9years) and 41 age-matched healthy controls (mean age: 45±8.2 years).Patients with hyperthyroidism had significantly higher serum fractalkine levels than healthy controls (p=0.01).Within the hyperthyroid group, fractalkine levels positively correlated with carotid intima-media thickness (CIMT), a marker of subclinical atherosclerosis (r=0.317,p=0.043), and negatively correlated with mitral annular velocity in late diastole (a'), a diastolic parameter indicative of HF with preserved ejection fraction (HFpEF) (r =-0.344, p=0.028).Linear regression analysis identified fractalkine as an independent predictor of increased CIMT and of reduced a'.Conclusions: This study demonstrated that fractalkine levels are elevated in patients with hyperthyroidism and are associated with early markers of CV dysfunction, including subclinical atherosclerosis and HFpEF.