Popular Class of Diabetes Drug Raises Bladder Cancer Risk

According to researchers from the University of Pennsylvania and the Perelman School of Medicine, patients taking thiazolidinediones (TZDs)—a class of drug that is prescribed for up to 20% of individuals with diabetes in the United States—are 2 to 3 times more likely to get bladder cancer than those taking sulfonylureas.

The research, published online in the Journal of the National Cancer institute, included 60,000 type 2 diabetes patients from the Health Improvement Network database in the United Kingdom. Based on their observations, the investigators concluded that 170 per 100,000 patients treated with TZDs (pioglitazone or rosiglitazone) for 5 or more years were expected to develop bladder cancer, whereas only 60 in 100,000 patients prescribed sulfonylureas were expected to develop the condition.

The authors note that diabetic patients are known to have a greater chance of developing this type of cancer compared with the general population. In addition, the FDA has warned the public that use of the diabetes medication pioglitazone for more than 1 year may be associated with an increased risk of bladder cancer.

“We believe our study will help doctors and their patients weigh the potential benefits and risks when selecting between different diabetes medications,” said the study’s lead author, Ronac Mamtani, MD, instructor in the Division of Hematology-Oncology in Penn’s Abramson Cancer Center.