The risk of sudden cardiac arrest and ventricular arrhythmia with rosiglitazone versus pioglitazone: real-world evidence on thiazolidinedione safety.

BACKGROUND: The low cost of thiazolidinediones makes them a potentially valuable therapeutic option for the > 300 million economically disadvantaged persons worldwide with type 2 diabetes mellitus. Differential selectivity of thiazolidinediones for peroxisome proliferator-activated receptors in the myocardium may lead to disparate arrhythmogenic effects. We examined real-world effects of thiazolidinediones on outpatient-originating sudden cardiac arrest (SCA) and ventricular arrhythmia (VA). METHODS: We conducted population-based high-dimensional propensity score-matched cohort studies in five Medicaid programs (California, Florida, New York, Ohio, Pennsylvania | 1999-2012) and a commercial health insurance plan (Optum Clinformatics | 2000-2016). We defined exposure based on incident rosiglitazone or pioglitazone dispensings; the latter served as an active comparator. We controlled for confounding by matching exposure groups on propensity score, informed by baseline covariates identified via a data adaptive approach. We ascertained SCA/VA outcomes precipitating hospital presentation using a validated, diagnosis-based algorithm. We generated marginal hazard ratios (HRs) via Cox proportional hazards regression that accounted for clustering within matched pairs. We prespecified Medicaid and Optum findings as primary and secondary, respectively; the latter served as a conceptual replication dataset. RESULTS: The adjusted HR for SCA/VA among rosiglitazone (vs. pioglitazone) users was 0.91 (0.75-1.10) in Medicaid and 0.88 (0.61-1.28) in Optum. Among Medicaid but not Optum enrollees, we found treatment effect heterogeneity by sex (adjusted HRs = 0.71 [0.54-0.93] and 1.16 [0.89-1.52] in men and women respectively, interaction term p-value = 0.01). CONCLUSIONS: Rosiglitazone and pioglitazone appear to be associated with similar risks of SCA/VA.

Adherence and Persistence with DPP-4 Inhibitors Versus Pioglitazone in Type 2 Diabetes Patients with Chronic Kidney Disease: A Retrospective Claims Database Analysis.

BACKGROUND: Adherence and persistence with diabetes medication play an important role in glycemic control and may differ by medication class. However, there is a lack of research comparing diabetes medications in patients with renal impairment, despite the challenges and higher burden associated with managing this population. OBJECTIVE: To compare adherence and persistence among patients with type 2 diabetes mellitus (T2DM) and nondialysis chronic kidney disease (CKD) treated with dipeptidyl peptidase-4 (DPP-4) inhibitors versus pioglitazone. METHODS: This retrospective cohort study used Truven MarketScan administrative claims databases from 2009 to 2015. One-year adherence for patients with T2DM and nondialysis CKD who initiated therapy with either a DPP-4 inhibitor or pioglitazone was measured by proportion of days covered (PDC) following an initial dispensing, and PDC ≥ 0.80 was coded as adherent. Persistence was calculated as the days between the index date and last day with the index medication on hand, based on the end of the last days supply or the end of follow-up (i.e., 365 days), whichever occurred first. Multivariate logistic regression and Cox proportional hazards models were used to estimate confounder-adjusted differences between the groups for adherence and persistence. RESULTS: The final cohort included 9,019 patients (DPP-4 inhibitors: 7,002; pioglitazone: 2,017). In the adjusted analysis, DPP-4 inhibitor users demonstrated a 1.41 (95% CI = 1.25-1.59) higher odds of being adherent compared with pioglitazone users. Overall adjusted HR for persistence was 0.74 (95% CI = 0.69-0.79), which favored DPP-4 inhibitors compared with pioglitazone. Relative to 2010, persistence with pioglitazone decreased in 2011-2012 and then increased in 2013-2014. In the subgroup analysis, DPP-4 inhibitors first had lower (2010: OR = 0.78, 95% CI = 0.70-0.87; 2011-2012: OR = 0.60, 95% CI = 0.54-0.66) and then similar (2013-2014: OR = 1.03, 95% CI = 0.88-1.19) hazards of nonpersistence compared with pioglitazone. CONCLUSIONS: Among patients with T2DM and nondialysis CKD, the use of DPP-4 inhibitors was associated with better adherence compared with pioglitazone. However, following the approval of generic pioglitazone and associated lower cost sharing after 2012, the magnitude of difference in adherence between the medication classes reduced. Similarly, safety warnings in 2011 and approval of generic products in 2012 may have affected pioglitazone persistence, leading to first higher and then similar hazards for nonpersistence with pioglitazone as compared with DPP-4 inhibitors. These shifts in the results for pioglitazone warrant further investigation and close monitoring of the population initiating this medication. DISCLOSURES: No funding was received for this study. The authors have no conflicts of interest to disclose. An abstract for this study was presented as a podium presentation at the International Society of Pharmacoeconomics and Outcomes Research (ISPOR) 2019 Annual Meeting; May 18-22, 2019; New Orleans, LA.

Study design choices for evaluating the comparative safety of diabetes medications: An evaluation of pioglitazone use and risk of bladder cancer in older US adults with type-2 diabetes.

AIM: The aim of the study was to empirically demonstrate the effect of varying study designs when evaluating the safety of pioglitazone in treating bladder cancer. METHODS: We identified Medicare beneficiaries above 65 years of age with diabetes between 2008 and 2015 and with classified exposure (at least two claims within 180 days) to glucose-lowering drugs (GLD), pioglitazone or another drug. The effects of varying the following study design parameters on bladder cancer risk were assessed: use of a new vs existing drug, choice of referent (all non-users and users of GLDs, non-insulin GLDs and DPP-4s) and whether or not censoring accounted for treatment change. We used the Cox proportional hazards model to obtain adjusted HRs and 95% CIs. RESULTS: We included 1,510,212 patients classified as pioglitazone users (N = 135,188) or non-users (N = 1,375,024). Users had more diabetic complications than non-users, but fewer than insulin users. The HR ranged from 1.10 (1.01-1.20) to 1.13 (0.99-1.29) when censoring ignored treatment change, suggesting a weak association or none between pioglitazone and bladder cancer, probably under-estimating risk. However, the HR was 1.20 (1.01-1.42) when cohorts were restricted to new users, censored upon treatment change, and when DPP-4 was used as the referent, suggesting an increased risk of bladder cancer associated with pioglitazone. CONCLUSIONS: The continued demand for new GLDs indicates the need for more robust observational methods to improve the value of generating real-world evidence in equipping clinicians to make informed prescribing decisions. Although there is no one-size-fits-all approach, we recommend active comparator new user study designs that compare therapeutically equivalent drugs and account for treatment changes during follow-up to present the least biased comparative safety estimates.

Pioglitazone: The forgotten, cost-effective cardioprotective drug for type 2 diabetes.

Type 2 diabetes individuals are at high risk for macrovascular complications: myocardial infarction, stroke and cardiovascular mortality. Recent cardiovascular outcome trials have demonstrated that agents in two antidiabetic classes (SGLT2 inhibitors and GLP-1 receptor agonists) reduce major adverse cardiovascular events. However, there is strong evidence that an older and now generically available medication, the thiazolidinedione, pioglitazone, can retard the atherosclerotic process (PERISCOPE and Chicago) and reduce cardiovascular events in large randomized prospective cardiovascular outcome trials (IRIS and PROactive). Pioglitazone is a potent insulin sensitizer, preserves beta-cell function, causes durable reduction in HbA1c, corrects multiple components of metabolic syndrome and improves nonalcoholic fatty liver disease/nonalcoholic steatohepatitis. Adverse effects (weight gain, fluid retention, fractures) must be considered, but are diminished with lower doses and are arguably outweighed by these multiple benefits. With healthcare expenses attributable to diabetes increasing rapidly, this cost-effective drug requires reconsideration in the therapeutic armamentarium for the disease.

Understanding medicines with a propensity to increase the risk of heart failure: Combining existing knowledge with targeted population assessment.

PURPOSE: Existing knowledge of medicines that increase the risk of an adverse event may be corroborated and augmented by population studies specifically assessing the risk associated with the concurrent use of these medicines and use by patients with existing comorbidity. An American Heart Association review recently identified a variety of medicines that may cause or exacerbate heart failure (HF), many with evidence from limited evaluation of population data. We assessed the risk of first-time HF associated with the use of 50 of these medicines by New Zealand's primary care population. METHODS: Case-control study utilising national pharmaceutical use and hospital admissions data 2007-2015; 22,989 patients with first-time HF 2008-2015 were matched with 114 498 control patients. The primary outcome was first-time HF and its association with medicine exposure in the prior 90 days, estimated using conditional logistic regression. We also assessed the risk associated with new use of medicines in the prior month, concurrent use, and in patients with existing comorbidity. RESULTS: Eleven medicines were significantly associated with HF with several other infrequently used medicines providing signals of increased risk. A high risk was associated with the use of salbutamol (adjusted odds ratio 2.63; 95% CI, 2.48-2.78), clozapine (2.70; 2.46-4.98), diltiazem (1.52; 1.44-1.60), indomethacin (2.51; 1.54-4.10), pioglitazone (1.50; 1.16-1.95), and antifungal medicines. New use of medicines and use of medicine combinations increased this risk in many cases. CONCLUSIONS: Our study provides further evidence to inform cautious use of these medicines in patients with HF or at risk of developing HF.