1. Department of Medicine, University of Illinois at Chicago, Chicago, IL, USA
2. Jesse Brown VA Medical Center, Chicago, IL, USA
3. Division of Epidemiology and Biostatistics, University of Illinois at Chicago, Chicago, IL, USA
4. Faculty of Health Sciences, Simon Fraser University, Burnaby, BC, Canada
5. Department of Kinesiology and Nutrition, University of Illinois at Chicago, Chicago, IL, USA
6. Department of Medicine, University of Chicago, Chicago, IL, USA