A common diabetes drug has been found to raise the risk of developing bladder cancer.
University of Alberta researchers who analyzed studies involving millions of patients determined pioglitazone, a medication used to treat type 2 diabetes, may significantly increase the risk of developing bladder cancer.
The study, published in the Canadian Medical Association Journal, also examined the effects of taking a second diabetes drug – rosiglitazone – but found no increased risk of bladder cancer in patients taking the medication. Both drugs are part of a class of medications called thiazolidinediones.
"We observed an increased risk of bladder cancer associated with the use of thiazolidinediones," said Dr. Jeffrey Johnson, with the University of Alberta School of Public Health. "In particular, use of pioglitazone was associated with an increased risk of bladder cancer based on a pooled estimate from three …studies involving more than 1.7 million individuals."
People with type 2 diabetes face greater cancer risk, including a 40 percent increased risk of bladder cancer, compared to people without the disease.
For the new study, researchers conducted a systematic review and meta-analysis of randomized controlled trials and observational studies involving more than 2.6 million patients.