Association between Coronary Flow Reserve, Klotho and Fibroblast Growth Factor 23 in Patients with Acromegaly

Abstract

Objectives: Acromegaly is a chronic endocrine disorder that is characterized by hypersecretion of growth hormone. The purpose of this study was to evaluate coronary flow reserve (CFR) in patients with acromegaly and investigate whether there is an association between fibroblast growth factor-23 (FGF-23) and Klotho levels with coronary micro-circulation or not. Methods: A total of 54 patients with acromegaly were divided into subgroups: Those with active disease and those who are in biochemical remission (serum insulin-like growth factor-1 level was within the normal range). Along with 31 healthy volunteers, the patients underwent dipyridamole-stress transthoracic Doppler echocardiography. CFR was calculated with the ratio of hyperemic to baseline diastolic peak velocities. Klotho and FGF-23 were measured using an enzyme-linked immunosorbent assay. Results: A total of 42 (%77.8) of acromegaly patients had active disease. Acromegaly patients had lower Klotho and FGF-23 levels compared to in controls. Patients with active disease had higher FGF-23 levels and lower Klotho levels when compared to patients in remission. CFR levels of active group were lower than remission and controls (p=0.001; p=0.043, respectively). Klotho was strongly associated with CFR levels in patients with active disease (r=0.8, p=0.001). Conclusion: Acromegaly patients have lower levels of Klotho and FGF-23 and CFR.