Diabetes drug doubles risk of bladder cancer

Patients who use pioglitazone, a drug for type 2 diabetes, every day for more than two years double their chances of developing the disease.

The medication for controlling blood sugar levels is known to increase the risk of heart failure, but the European Medicines Agency decided the benefits outweighed the risks.

Researchers based in Canada analysed the medical records of more than 115,000 people across the UK who were given the drug over an 11-year period and found that 470 patients were diagnosed with bladder cancer during the follow-up, a rate of 89 per 100,000 person years. The rate in the general UK population aged at least 65 is 73 per 100,000 person years.

Pioglitazone is similar to another drug, rosiglitazone, which does not increase bladder cancer risks.