A retrospective study to assess the risk of bladder cancer in type-2 diabetic patients treated with pioglitazone

INTRODUCTION: Pioglitazone has been a cornerstone of oral hypoglycemic therapy. Concerns have been raised about its association with urinary bladder cancer. Considering the wide usage of this drug, concrete and multiple population-based studies are needed to establish the safety of this drug. The present retrospective study is aimed to assess the association of pioglitazone with urinary bladder cancer. MATERIALS AND METHODS: Clinical records of 4170 patients (2085 pioglitazone users and similar number of nonpioglitazone users) attending the diabetes clinic at a tertiary level teaching hospital were accessed, and the patients were subjected to symptom-directed questionnaire, urine examination, and cystoscopy and bladder biopsy (whenever clinically indicated). The risk of bladder cancer was also assessed with respect to cumulative dose and duration of pioglitazone. RESULTS: We did not observe any increased risk of bladder malignancy with pioglitazone exposure; furthermore, there was no association with cumulative dose and duration of pioglitazone therapy. Pioglitazone was found to be effective and safe in managing glycemic control in diabetic patients.