Cardiovascular risk in users of mirabegron compared with users of antimuscarinic treatments for overactive bladder

Abstract

Introduction During clinical trials, mirabegron, a beta 3-adrenoreceptor agonist, was associated with increased vital signs vs placebo in patients with overactive bladder. Objective The purpose of this study was to compare incidence rates of adverse cardiovascular (CV) outcomes following mirabegron or antimuscarinic use. Methods We conducted an observational post-marketing safety study utilising real-world data. The study population was identified within five sources: Danish and Swedish National Registers, Clinical Practice Research Datalink (UK), Optum (USA) and Humana (USA). Episodes of time when patients were new users of mirabegron or antimuscarinics (October 2012-December 2018) were sourced from prescriptions and matched on propensity scores. Occurrences of major adverse cardiovascular events (MACE), acute myocardial infarction (AMI), stroke, CV mortality and all-cause mortality were identified. Outcome incidence rates and hazard ratios from Cox models were estimated. Results Overall, 152,026 mirabegron and 152,026 antimuscarinic episodes were matched. The population consisted of 63.1% women and 72.6% were >= 65 years old. There were no appreciable differences in the incidence rates of MACE, AMI or stroke between users of mirabegron and antimuscarinics. Incidence rates of CV mortality (hazard ratio 0.83, 95% confidence interval 0.73-0.95) and all-cause mortality (hazard ratio 0.80, 95% confidence interval 0.76-0.84) were no higher with mirabegron vs antimuscarinics. Results restricted to episodes at high risk for CV events or stratified by age (< 65 years, >= 65 years) or prior overactive bladder medication use were consistent with overall findings. Conclusions This large, multinational study found no higher risk of MACE, AMI, stroke, CV mortality or all-cause mortality among users of mirabegron relative to users of antimuscarinics.Plain Language Summary During clinical trials, mirabegron, which is a treatment for overactive bladder, was associated with small increases in heart rate and blood pressure. This study was conducted to compare the frequency of cardiac events following the use of mirabegron or antimuscarinics, a group of treatments also used to treat overactive bladder. We obtained the data for this study from four countries: Denmark, Sweden, the UK and the USA. We identified people who were new users of mirabegron or antimuscarinics from 2012 to 2018 using prescription or dispensing records. Occurrences of major cardiac events, heart attack, stroke, death due to cardiac events and death from any cause were evaluated. Overall, we identified 152,026 times when mirabegron or antimuscarinics were each used as new treatments. Most of the people in the study were women (63.1%) and at least 65 years old (72.6%). There were no notable differences between the treatment groups with regard to how often major cardiac events, heart attack or stroke occurred. Further, death due to cardiac events and death from any cause were no higher with mirabegron compared with antimuscarinics. We obtained similar results when the data were assessed for patients who were at high risk for cardiac events or split by age (less than 65 years or at least 65 years) or a history of overactive bladder medication use. In conclusion, this large study involving data from several countries found no higher risk of major cardiac events, heart attack, stroke or death among people prescribed mirabegron compared with antimuscarinics.