SEATTLE — How do oral hypoglycemic medications for type 2 diabetes affect overall mortality?
Concerned that few studies had been done on the drugs’ comparative safety, researchers from the VA Puget Sound Health Care System in Seattle sought to answer that question. The results, based on a comparison of mortality risk with monotherapy initiation of four oral hypoglycaemic medications in a nationwide cohort of U.S. veterans with type 2 diabetes, were published online recently by the journal Diabetologia.1
“Significantly higher mortality was associated with glibenclamide, glipizide and rosiglitazone use compared with metformin, and with glipizide use compared with rosiglitazone or glibenclamide,” the authors reported, adding that “the potential for residual confounding by indication should be considered in interpreting these results.”
For the study, researchers identified new users of oral hypoglycaemic medication monotherapy between 2004 and 2009 who received care for at least a year at the VHA. Follow-up within the study period continued until patients either ended their initial monotherapy, had an additional diabetes pharmacotherapy added or died.
Results indicated that among new users of metformin sulfonylureas and rosiglitazone representing 185,360 men and 7,812 women, 2.2% (4,256) died during follow-up. Average duration of medication use ranged from 1.4 to 1.7 years.
Study authors pointed out that significantly higher mortality risk was seen for glibenclamide, sold as glyburide in the U.S. and Canada, or glipizide compared with metformin monotherapy. That also was the case with glipizide compared with rosiglitazone or glibenclamide monotherapy.
In the case of rosiglitazone compared with metformin monotherapy, women had a higher risk of death (HR 4.36, 95% CI 1.34, 14.20) than men (HR 1.19, 95% CI 0.95, 1.49).
Study authors called for more research on the comparative safety of commonly employed diabetes drugs.
1.Wheeler S, Moore K, Forsberg CW, Riley K, Floyd JS, Smith NL, Boyko EJ.
Mortality among veterans with type 2 diabetes initiating metformin, sulfonylurea or rosiglitazone monotherapy. Diabetologia. 2013 Jun 25. [Epub ahead of print]PubMed PMID: 23797633.