1. From the Internal Medicine Service, Addiction Unit, Hospital Universitari Germans Trias i Pujol, Universitat Autonoma de Barcelona, Badalona, Spain (D.F.); and the Clinical Addiction Research and Education Unit, Section of General Internal Medicine, Department of Medicine, Boston Medical Center and Boston University School of Medicine, the Grayken Center for Addiction, Boston Medical Center, and the Department of Community Health Sciences, Boston University School of Public Health — all in Boston ( J.H.S.).