The Close Link of Pancreatic Iron With Glucose Metabolism and With Cardiac Complications in Thalassemia Major: A Large, Multicenter Observational Study.

Abstract

We systematically explored the link of pancreatic iron with glucose metabolism and with cardiac complications in a cohort of 1,079 patients with thalassemia major (TM) enrolled in the Extension-Myocardial Iron Overload in Thalassemia (E-MIOT) project. MRI was used to quantify iron overload (T2* technique) and cardiac function (cine images) and to detect macroscopic myocardial fibrosis (late gadolinium enhancement technique). Glucose metabolism was assessed by the oral glucose tolerance test (OGTT). Patients with normal glucose metabolism showed significantly higher global pancreas T2* values than patients with impaired fasting glucose, impaired glucose tolerance, and diabetes. A pancreas T2* <13.07 ms predicted an abnormal OGTT. A normal pancreas T2* value showed a 100% negative predictive value for disturbances of glucose metabolism and for cardiac iron. Patients with myocardial fibrosis showed significantly lower pancreas T2* values. Patients with cardiac complications had significantly lower pancreas T2* values. No patient with arrhythmias/heart failure had a normal global pancreas T2*. Pancreatic iron is a powerful predictor not only for glucose metabolism but also for cardiac iron and complications, supporting the close link between pancreatic iron and heart disease and the need to intensify iron chelation therapy to prevent both alterations of glucose metabolism and cardiac iron accumulation.