DPP4 and diabetes mellitus: Ninety-five of 461 patients had a known history of diabetes (20.61%), with 56 (58.95%) patients on only insulin therapy, 25 (26.32%) on oral antidiabetic agents (including metformin, sulfonylureas and dipeptidyl peptidase 4-inhibitors), and 11 (11.58%) on a combination of insulin and orals.