1. Division of Pulmonary Sciences and Critical Care Medicine, University of Colorado, Aurora, Colorado, USA
2. Center of Excellence for Substance Abuse Treatment and Education, Department of Veterans Affairs Puget Sound Health Care System, Seattle, Washington, USA
3. Health Services Research and Development, Department of Veterans Affairs Puget Sound Health Care System, Seattle, Washington, USA
4. Division of Cardiology, Department of Medicine, Denver VA Medical Center, Denver, Colorado, USA
5. Department of Medicine, Division of Cardiology, University of Colorado, Aurora, Colorado, USA
6. Group Health Research Institute, Seattle, Washington, USA