Diabetes drug found to raise risk of bladder cancer

A drug used in the treatment of diabetes might raise the risk of bladder cancer, according to a new study. The study added that the risk increased with the rising duration of use and the dose.

Pioglitazone is among a class of drugs called thiazolidinediones and helps to patients with type 2 diabetes to control blood sugar levels. However, according to the findings of the study, taking the drug increased risk of bladder cancer by 63 per cent.

In a trial in 2005, a number of blood cancer cases were identified among people who took the drug. However, different studies, since then had reported contradictory findings on the subject.

The use of the drug was examined by Canada-based researchers who found an increased association of risk of bladder cancer in patients with type 2 diabetes.

Data related to 145,806 patients from the UK's Clinical Practice Research Database (CPRD) was examined by the team. The patients were newly treated with diabetes drugs between 2000 and 2013.

A number of other factors that could be influential such as age, sex, duration of diabetes, smoking status and alcohol-related disorders were also factored in.

As against the drug, use of rosiglitazone did not carry increased risk of bladder cancer in any analysis, suggesting the risk was drug-specific and not a class effect, according to the researchers who published the study published in the journal The BMJ.

In another large cohort study, experts from University of Nottingham in the UK uncovered clinically important differences between different drugs (alone and in combination) and risk of five key outcomes - blindness, amputation, severe kidney failure, high blood sugar (hyperglycaemia) and low blood sugar (hypoglycaemia) events.

The results might have implications for prescribing, and researchers suggest doctors and patients need to be aware when assessing the overall risks and benefits of diabetes drugs, the researchers pointed out.