1. Division of Gastroenterology & Hepatology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
2. Department of Preventive Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
3. Division of Cardiology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
4. Department of Epidemiology, University of Alabama at Birmingham, Birmingham, AL 35294, USA
5. Department of Radiology, Vanderbilt University Medical Center, Nashville, TN 37232, USA