Meta-analysis confirms raised risk of bladder cancer from pioglitazone

A new meta-analysis1 seems to confirm findings from a nested, case-control study published in the BMJ in May2 that thiazolidinediones are associated with an increased risk of bladder cancer in people with type 2 diabetes.

Both analyses also found that in the studies that looked at individual drugs in this class pioglitazone, but not rosiglitazone, was associated with an increased risk of bladder cancer.

In the BMJ study, Azoulay and colleagues from McGill University in Montreal looked at a cohort that included 115 727 new users of oral hypoglycaemic agents, of whom 470 were given a diagnosis of bladder cancer during follow-up …