No association found between thiazolidinediones and bladder cancer

the Oncology Nurse Advisor take:

According to a new study published in the journal Diabetologia, there is no link between either pioglitazone or rosiglitazone and bladder cancer.

For the study, the researchers collected prescription, cancer, and mortality data from 1.01 million people with type 2 diabetes from six populations in Europe and North America. Of those, 3,248 developed bladder cancer and only 117 of those were in patients who had taken pioglitazone. 

Results showed that there was no link between cumulative exposure to the thiazolidinediones and bladder cancer in men or women after adjustment for other factors. In addition, longer exposure to pioglitazone did no increase the risk for developing bladder cancer.

According to the American Cancer Society, there will be an estimated nearly 75,000 new cases of bladder cancer and about 15,600 deaths from the disease. Men are about 3 to 4 times more likely to develop bladder cancer than women, but that risk is about 1 in 26 men.

Previous studies have shown that drugs from this class of antidiabetic drugs increases the risk of bladder cancer, but this study demonstrates otherwise. The authors suggest that studies with a longer duration of follow-up of patients exposed to pioglitazone or rosiglitazone be conducted to end the controversy.