Search

Pioglitazone has been reported to increase the risk of bladder cancer but the conclusions of published clinical studies are confusing. We conducted a systematic review and meta-analysis of all eligible randomized controlled trial (RCT) studies and observational studies, in order to identify a more precise relationship between pioglitazone and risk of bladder cancer. We searched for publications up to January 24, 2018, in PubMed, EMBASE, Scopus, Web of Science, Cochrane register, and Chinese National Knowledge Infrastructure databases, and the references of the retrieved articles and relevant reviews were also checked. Relative risk and 95% confidence interval (CI) were used to assess this correlation. A dose-related meta-analysis was performed as well. Data on RCT studies showed a null association between pioglitazone and bladder cancer. The pooled RR estimates of the 12 included studies illustrated that pioglitazone is associated with a 14% increased risk of bladder cancer (95% CI 1.03–1.26). No evidence of publication bias was detected. In the dose effect analysis, patients who used a higher dose of pioglitazone had an increased risk of bladder cancer. In conclusion, this meta-analysis indicated that pioglitazone is associated with an increased risk of bladder cancer. Further research should be conducted to confirm our findings and reveal the potential biological mechanisms. [ABSTRACT FROM AUTHOR]

Abstract: Current evidence about the association between pioglitazone and bladder cancer risk remains conflict. We aimed to assess the risk of bladder cancer associated with the use of pioglitazone and identify modifiers that affect the results. We systematically searched PubMed, Embase, and Cochrane Central Register of Controlled Trials from inception to 25 August 2016 for randomized controlled trials (RCTs) and observational studies that evaluated the association between pioglitazone and bladder cancer risk. Conventional and cumulative meta‐analyses were used to calculate the odds ratio (OR) with 95% confidence interval (CI). A restricted spline regression analysis was used to examine the dose–response relationship with a generalized least‐squares trend test. We included two RCTs involving 9114 patients and 20 observational studies (n = 4,846,088 individuals). An increased risk of bladder cancer in patients treated with pioglitazone versus placebo was noted from RCTs (OR, 1.84; 95%CI, 0.99 to 3.42). In observational studies, the increased risk of bladder cancer was slight but significant among ever‐users of pioglitazone versus never‐users (OR, 1.13; 95%CI, 1.03 to 1.25), which appeared to be both time‐ (P = 0.003) and dose‐dependent (P = 0.05). In addition, we observed the association differed by region of studies (Europe, United States, or Asia) or source of funding (sponsored by industry or not). Current evidence suggests that pioglitazone may increase the risk of bladder cancer, possibly in a dose‐ and time‐dependent manner. Patients with long‐term and high‐dose exposure to pioglitazone should be monitored regularly for signs of bladder cancer. [ABSTRACT FROM AUTHOR]

Aim: We performed a meta-analysis of epidemiological studies evaluating exposure to pioglitazone and the risk for bladder cancer and compared these results to the drug's effects on cardiovascular disease (CVD) and non-alcoholic steatohepatitis (NASH).Methods: Pubmed and Embase were searched for cohort and case control studies for all years through 2016.Results: Data from 17 papers were analyzed. In cohort studies, 822 of 357,888 pioglitazone-exposed patients (0.23%) developed bladder cancer while 7691 of 2,898,682 unexposed (0.26%) did. In case control studies, 3219 of 1,146,916 patients (0.28%) developed bladder cancer. A random effects model showed no significant association between ever vs never use or with cumulative doses of pioglitazone. However, there was a significant association with 1-2 years (HR = 1.28 [1.08-1.55]) and >2 years (HR = 1.42 [1.14-1.77]) of exposure. The numbers needed to treat for one additional case of bladder cancer ranged from 899 to 6380 while to benefit CVD and NASH, 4-256 and 2-12, respectively.Conclusions: Given the very small prevalence of bladder cancer in diabetic patients exposed (or not) to pioglitazone (<0.3%) and the much greater beneficial effects of the drug on CVD and NASH, the use of pioglitazone should be resurrected. [ABSTRACT FROM AUTHOR]

People with type 2 diabetes are at increased risk of bladder cancer. Pioglitazone is said to increase it further, although published evidence is mixed. We conducted a meta-analysis to determine if any link between the use of pioglitazone and an increased risk of bladder cancer can be found. A comprehensive literature search was conducted through electronic databases as well as registries for data of clinical trials to identify studies that investigate the effect of pioglitazone on bladder cancer in diabetic patients. We used the risk ratio (RR) and the hazard ratio (HR) provided by the studies to illustrate the risk of occurrence of bladder cancer in the experimental group compared to that in the control group. Fourteen studies using RR and 12 studies using HR were included in the analysis. The overall RR was 1.13 with 95% CI (0.96-1.33) with low heterogeneity among the studies using RR, suggesting that no connection exists between use of pioglitazone and the risk of bladder malignancy. The summary HR was 1.07 (0.96-1.18) allowing us to affirm that there is no link between long-term use of pioglitazone and bladder cancer. Our results support the hypothesis of no difference in the incidence of bladder cancer among the pioglitazone group and the nonuser group. Our conclusion is that the explanation of hypothetically increased risk of bladder malignancy should be attributed to other factors. Funding : Tchaikapharma High Quality Medicines Inc. [ABSTRACT FROM AUTHOR]

IMPORTANCE Studies suggest pioglitazone use may increase risk of cancers. OBJECTIVE To examine whether pioglitazone use for diabetes is associated with risk of bladder and 10 additional cancers. DESIGN, SETTING, AND PARTICIPANTS Cohort and nested case-control analyses among persons with diabetes. A bladder cancer cohort followed 193 099 persons aged 40 years or older in 1997-2002 until December 2012; 464 case patients and 464 matched controls were surveyed about additional confounders. A cohort analysis of 10 additional cancers included 236 507 persons aged 40 years or older in 1997-2005 and followed until June 2012. Cohorts were from Kaiser Permanente Northern California. EXPOSURES Ever use, duration, cumulative dose, and time since initiation of pioglitazone as time dependent. MAIN OUTCOMES AND MEASURES Incident cancer, including bladder, prostate, female breast, lung/bronchus, endometrial, colon, non-Hodgkin lymphoma, pancreas, kidney/renal pelvis, rectum, and melanoma. RESULTS Among 193 099 persons in the bladder cancer cohort, 34 181 (18%) received pioglitazone (median duration, 2.8 years; range, 0.2-13.2 years) and 1261 had incident bladder cancer. Crude incidences of bladder cancer in pioglitazone users and nonusers were 89.8 and 75.9 per 100 000 person-years, respectively. Ever use of pioglitazone was not associated with bladder cancer risk (adjusted hazard ratio [HR], 1.06; 95% CI, 0.89-1.26). Results were similar in case-control analyses (pioglitazone use: 19.6% among case patients and 17.5% among controls; adjusted odds ratio, 1.18; 95% CI, 0.78-1.80). In adjusted analyses, there was no association with 8 of the 10 additional cancers; ever use of pioglitazone was associated with increased risk of prostate cancer (HR, 1.13; 95% CI, 1.02-1.26) and pancreatic cancer (HR, 1.41; 95% CI, 1.16-1.71). Crude incidences of prostate and pancreatic cancer in pioglitazone users vs nonusers were 453.3 vs 449.3 and 81.1 vs 48.4 per 100 000 person-years, respectively. No clear patterns of risk for any cancer were observed for time since initiation, duration, or dose. CONCLUSIONS AND RELEVANCE Pioglitazone use was not associated with a statistically significant increased risk of bladder cancer, although an increased risk, as previously observed, could not be excluded. The increased prostate and pancreatic cancer risks associated with ever use of pioglitazone merit further investigation to assess whether they are causal or are due to chance, residual confounding, or reverse causality. [ABSTRACT FROM AUTHOR]

Aims To determine whether thiazolidinedione use is associated with a risk of bladder cancer. Methods We searched MEDLINE and EMBASE in June 2012 (with Pub Med update to July 2013) and conducted meta-analysis on the overall risks of bladder cancer with pioglitazone or rosiglitazone and the risk with different categories of cumulative dose or duration of drug use. Results We screened 230 citations and included 18 studies, comprising five randomized controlled trials ( RCTs) and 13 observational studies. Meta-analysis showed a significantly higher overall risk of bladder cancer with pioglitazone in RCTs [7878 participants; odds ratio ( OR) 2.51, 95% confidence interval ( CI) 1.09-5.80] and observational studies (>2.6 million patients; OR for 'ever' users vs. non-users 1.21, 95% CI 1.09-1.35). Subgroup analysis of observational studies by cumulative dose showed the risk of bladder cancer to be greatest with >28.0 g of pioglitazone ( OR 1.64, 95% CI 1.28-2.12). A significantly increased risk was found with both 12-24 months ( OR 1.41, 95% CI 1.16-1.71) and >24 months ( OR 1.51, 95% CI 1.26-1.81) cumulative durations of pioglitazone exposure. No significant risk was seen with rosiglitazone in RCTs ( OR 0.84, 95% CI 0.35-2.04) or 'ever' users vs. non-users in observational studies ( OR 1.03, 95% CI 0.94-1.12); the evidence for any relationship between bladder cancer risk and rosiglitazone cumulative duration is limited and inconsistent. Direct comparison of pioglitazone to rosiglitazone 'ever' users yielded an OR of 1.25 (95% CI 0.91-1.72). Conclusions A modest but clinically significant increase in the risk of bladder cancer with pioglitazone was found, which appears to be related to cumulative dose and duration of exposure. We recommend that prescribers limit pioglitazone use to shorter durations. [ABSTRACT FROM AUTHOR]

There is a concern of an increased risk of bladder cancer associated with the use of thiazolidinediones, a class of oral glucose-lowering drugs commonly used in patients with type 2 diabetes with a mechanism of improving insulin resistance. Human studies on related issues are reviewed, followed by a discussion on potential concerns on the causal inference in current studies. Pioglitazone and rosiglitazone are discussed separately, and findings from different geographical regions are presented. Randomized controlled trials designed for primarily answering such a cancer link are lacking, and evidence from clinical trials with available data for evaluating the association may not be informative. Observational studies have been reported with the use of population-based administrative databases, single-hospital records, drug adverse event reporting system, and case series collection. Meta-analysis has also been performed by six different groups of investigators. These studies showed a signal of higher risk of bladder cancer associated with pioglitazone, especially at a higher cumulative dose or after prolonged exposure; however, a weaker signal or null association is observed with rosiglitazone. In addition, there are some concerns on the causal inference, which may be related to the use of secondary databases, biases in sampling, differential detection, and confounding by indications. Lack of full control of smoking and potential biases related to study designs and statistical approaches such as prevalent user bias and immortal time bias may be major limitations in some studies. Overlapping populations and opposing conclusions in studies using the same databases may be of concern and weaken the reported conclusions of the studies. Because randomized controlled trials are expensive and unethical in providing an answer to this cancer issue, observational studies are expected to be the main source in providing an answer in the future. Furthermore, international comparison studies using well-designed and uniform methodology to clarify the risk in specific sexes, ethnicities, and other subgroups and to evaluate the interaction with other environmental risk factors or medications will be helpful to identify patients at risk. [ABSTRACT FROM PUBLISHER]

Background: There is growing concern regarding the increased incidence of bladder cancer in diabetic patients using pioglitazone. This study aimed to investigate the association between bladder cancer and the use of pioglitazone in Korean diabetics. Methods: This retrospective, matched case-control study included a case group (n = 329) of diabetic patients with bladder cancer who presented at the Severance Hospital from November 2005 to June 2011. The control group consisted of patients without bladder cancer (1:2 ratio matching for sex and age, n = 658) who were listed on the Severance Hospital diabetes registry. Results: The percentage of subjects who had ever used pioglitazone was significantly lower in the case group than in the control group (6.4% vs. 15.0%, P<0.001). Multivariate conditional logistic analysis revealed that independent factors affecting bladder cancer were smoking (odds ratio [OR], 11.64; 95% confidence interval [CII, 6.56 to 20.66; P<0.001), coexisting cancer (OR, 6.11; 95% CI, 2.25 to 16.63; P<0.001), and hemoglobin levels (OR, 0.78; 95% CI, 0.69 to 0.88; P<0.001). The OR of the history of pioglitazone use was 2.09 and was not significantly different between the two groups (95% CI, 0.26 to 16.81; P=0.488). Conclusion: A relationship between pioglitazone use and incidence of bladder cancer was not observed in Korean diabetic patients. This suggests that the risk for bladder cancer in Korean diabetic subjects treated with pioglitazone might be different from that of Caucasian populations. Large-scale, well-designed and multi-center studies are needed to further evaluate this relationship. [ABSTRACT FROM AUTHOR]

This article reviews human observations on pioglitazone and bladder cancer risk. The PROspective pioglitAzone Clinical Trial In macroVascular Events trial showed an imbalance in bladder cancer between users of pioglitazone and placebo (14 versus six cases, p = 0.069). However, after excluding bladder cancer probably ascribed to other etiology, a blind assessment concluded that the imbalance might not be related to pioglitazone. Epidemiologic studies conducted in the United States and France using insurance databases independently suggested that pioglitazone use for >2 years might confer a 20%–40% higher risk. Another study evaluating bladder cancer risk in diabetic patients using the National Health Insurance in Taiwan did not find any incident bladder cancer case among 422 pioglitazone users for a follow-up of up to 3 years. Because observational studies may suffer from selection and information bias, and inadequate adjustment for confounders may inflate the estimated risk, causal inference from these studies should be interpreted with caution. While investigating cancer risk associated with a medication, indication bias should also be attended, especially when the medication is used at a late stage of the disease. Because pioglitazone is usually a second or third line antidiabetic agent, the users are always characterized by older age, longer diabetes duration, poorer glycemic control, and higher rates of complications and comorbidities. Biased estimates will also result if these differences are not appropriately addressed in the analyses. Current evidence neither concludes nor excludes a causal role of pioglitazone on bladder cancer. Clinical trials aiming at evaluating the risk of cancer associated with a medication is not ethical and may not be expected to provide an answer on the issue of pioglitazone-related bladder cancer. However, a meta-analysis using all available clinical trials to compare the bladder cancer risk between pioglitazone and comparators will be helpful. Well-conducted epidemiologic observational studies are probably other options. Because bladder cancer incidence and their risk factors may differ significantly among different ethnicities, a clarification of such a link in different ethnicities is needed, better by using long-term databases with large and representative sample size and appropriate adjustment for confounders. Furthermore, the interactions with other comorbidities and concomitant medications should be addressed. [ABSTRACT FROM AUTHOR]

Abstract: Pioglitazone hydrochloride (PIO), a peroxisome proliferator-activated receptor gamma (PPARγ) agonist, was administered orally for 85weeks at 16mg/kg/day to male rats fed either a diet containing 1.5% ammonium chloride (acid-forming diet) or a control diet to investigate the effects of urinary acidification induced by the acid-forming diet on the tumorigenic potential of PIO in the urinary bladder. The surviving animals at the end of the administration period were followed to the end of the 2-year study period without changes in the diet and were subjected to terminal necropsy on Week 104. The number of urinary microcrystals, evaluated by manual counting with light microscopy and by an objective method with a laser diffraction particle size analyzer, was increased by PIO on Weeks 12 and 25 and the increases were markedly suppressed by urinary acidification. Urinary citrate was decreased by PIO throughout the study period, but no changes were seen in urinary oxalate at any timepoint. The incidences of PIO-treated males bearing at least one of the advanced proliferative changes consisting of papillary hyperplasia, nodular hyperplasia, papilloma or carcinoma were significantly decreased from 11 of 82 males fed the control diet to 2 of 80 males fed the acid-forming diet. The acid-forming diet did not show any effects on the toxicokinetic parameters of PIO and its metabolites. Microcrystalluria appears to be involved in the development of the advanced stage proliferative lesions in bladder tumorigenesis induced by PIO in male rats. [Copyright &y& Elsevier]

The authors examine the case of the oral hypoglycemic agent pioglitazone which is involved in a controversy regarding its safety despite its efficacy. They discuss a few basic principles of pharmacology and pharmaco-epidemiology and the possible association between the drug and bladder cancer. They also mention the importance of pharmacovigilance in ensuring patient safety.

OBJECTIVE--The association between pioglitazone and bladder cancer has not been investigated in Asians. We aimed to investigate this association. RESEARCH DESIGN AND METHODS--A total of 1,000,000 individuals were randomly sampled from the National Health Insurance database, and incident cases of bladder cancer during the period from 1 January 2006 to 31 December 2009 were analyzed among 54,928 patients with type 2 diabetes and without previous bladder cancer. RESULTS--Among 165 incident case subjects, 10 (0.39%) were ever users and 155 (0.30%) were never users of pioglitazone (adjusted hazard ratio in full model 1.305 [95% CI 0.661-2.576]). All bladder cancer in ever users occurred within a duration of therapy <24 months, suggesting an early effect of pioglitazone on bladder cancer or late use of pioglitazone in high-risksex patients. CONCLUSIONS--The association between pioglitazone and bladder cancer was not significant. However, confirmation of this finding is required because of the possible lack of statistical power owing to the small number of events. [ABSTRACT FROM AUTHOR]

Aims To compare bladder cancer incidence between patients initiating pioglitazone treatment and patients initiating treatment with dipeptidyl-peptidase-4 inhibitors [DPP-4s] or sulfonylureas. Methods We identified Medicare beneficiaries aged >65 years who initiated treatment with pioglitazone ( N = 38 700), DPP-4s ( N = 82 552) or sulfonylureas ( N = 126 104) between 2007 and 2014 after at least 6 months without prescriptions for these drug classes. Patients were followed from second prescription until bladder cancer outcome (2 claims within 60 days) using a 6-month induction/latency period, censoring for treatment change, death or end of 2014. We used propensity score-weighted Cox proportional-hazards models to obtain adjusted hazard ratios (a HR) and their 95% confidence intervals. Results Overall mean age of participants was 75 years and 41% were men. Over a median of 1.2 treatment years, 727 beneficiaries developed bladder cancer. Pioglitazone initiators had an increased incidence of bladder cancer (308 vs 204 [DPP-4s] or 231 [sulfonylureas] per 100 000 person-years; aHR, 1.57 [1.23-2.00] vs DPP-4s and 1.32 [1.02-1.70] vs sulfonylureas). The increased risk emerged within the first 2 years of treatment (aHR, 1.63 [1.22-2.17] vs DPP-4s and 1.32 [0.98-1.78] vs sulfonylureas). If treatment was discontinued within the first 2 years, the risk after 2 years post initiation was attenuated (aHR, 0.89 [0.61-1.28]) compared with patients treated for more than 2 years (aHR, 1.45 [0.93-2.26]) both vs DPP-4s. Findings were consistent across secondary and sensitivity analyses. Conclusions Pioglitazone was associated with an elevated risk of bladder cancer compared with DPP-4s and sulfonylureas. The elevated risk emerged within the first 2 years of treatment and was attenuated after discontinuing. Pioglitazone's relative effectiveness should be weighed against a small absolute increase in risk of bladder cancer. [ABSTRACT FROM AUTHOR]

An online continuing medical education quiz about the risk of pioglitazone use for bladder cancer in patients with diabetes is presented.

The article discusses research about the link between the use of pioglitazone of patients with diabetes and bladder cancer risk. Topics mentioned include the implications of adverse events on public health, the warning issued by the U.S. Food and Drug Administration (FDA) about the use of pioglitazone in patients with a previous history of bladder cancer, and the role of the periodical in providing information about the safety of drugs to improve public health.

The article discusses research about the safety of pioglitazone in the management of patients with diabetes. Topics mentioned include the association between the use of pioglitazone and bladder cancer risk, recommendations by the Institute of Medicine for the U.S. Food and Drug Administration (FDA) to employ a consistent decision making framework for the determination of the life cycle, benefits, and risks of drugs, and a key quality of FDA decision making.

The article comments on a study by D. Levin and colleagues, published in "Diabetologia" which investigated whether the use of glitazones is associated with an increased risk of bladder cancer. Topics discussed include the incidence of bladder cancer worldwide, the function of pioglitazone and rosiglitazone as peroxisome proliferator-activated receptor (PPAR) gamma agonists, and the withdrawal of pioglitazone in Germany and France.

A response from the author of the article "Risk of Bladder Cancer in Korean Diabetic Subjects Treated with Pioglitazone" in the 2012 issue is presented.

A letter to the editor is presented in response to the article "Risk of Bladder Cancer in Korean Diabetic Subjects Treated with Pioglitazone" in the 2012 issue.

The author reflects on what prompted a guidance on pioglitazone to change and the overall risks and benefits of the drug. He cites several studies suggesting that pioglitazone will have a small increased risk of bladder cancer. He describes the fundamental changes to the product information for pioglitazone, a valid treatment option for certain patients with type 2 diabetes.

The article provides an answer to a question on whether there is a link between increased risk of bladder cancer and pioglitazone use in patients with type 2 diabetes mellitus.

Use of pioglitazone for more than a year may be associated with an increased risk of bladder cancer. Consider the risk of bladder cancer when prescribing pioglitazone. Avoid pioglitazone in patients with bladder cancer or a history of bladder cancer. Ask patients taking pioglitazone to report blood in the urine, urinary urgency, pain on urination, and back or abdominal pain. [ABSTRACT FROM AUTHOR]

The article examines the association of diabetes treatment with pioglitazone and a small increased risk of bladder cancer. It discuses the adverse effect of pioglitazone drug. It cites several studies suggesting that pioglitazone will have a small increased risk of bladder cancer. It offers advice when starting to use pioglitazone to treat diabetes.