1 From the Department of Psychiatry, Mathison Centre for Mental Health Research and Education, Hotchkiss Brain Institute, University of Calgary, Calgary, Alta. (MacQueen); the Department of Biochemistry and Biomedical Sciences and Department of Medicine (Gastroenterology), McMaster University, Hamilton, Ont. (Surette); and the Division of Gastroenterology and Audrey Campbell Chair in Ulcerative Colitis Research, Department of Medicine, McMaster University, Hamilton, Ont. (Moayyedi).