Simspon SH, Majumdar SR, Tsuyuki RT, Eurich DT, Johnson JA. Dose-response relation between sulfonylurea drugs and mortality in type 2 diabetes mellitus: a population-based cohort study. CMAJ. 2006; 174: 169-174, 185-86.

Canadian researchers recently reported a dose-related link between sulfonylurea use and mortality in type 2 diabetes patients. In previous studies, the authors had shown that metformin presents a survival advantage over sulfonylureas. It was unclear, however, if this was due to a protective effect of metformin or from a potentially adverse effect from the sulfonylureas. In this recent study, the researchers analyzed 5,795 subjects who were prescribed a first-ever oral antidiabetic agent and were entered in the Saskatchewan Health databases between 1991 and 1999. The goal was to ascertain whether or not a dose-response relation existed between sulfonylurea use and death. The average age of patients was 66.3 years, and 43.4% were female. The patients were followed for a mean of 4.6 years. The antidiabetic agents used included first-generation sulfonylureas for 120 subjects, glyburide for 4,138, and metformin for 1,537. At higher daily doses, sulfonylureas and, to a lesser extent, glyburide were associated with an increased risk of death. A dose-response relationship was not indicated with metformin.