Number needed to treat in cardiovascular outcome trials of glucagon-like peptide-1 receptor agonists: A systematic review with temporal analysis

Cardiovascular outcome trials (CVOTs) investigating the safety and efficacy of glucagon-like peptide-1 receptor agonists (GLP-1RAs) have highlighted some important differences among these medications. The recent American Diabetes Association and European Association for the Study of Diabetes consensus underlines that each trial constitutes a single experiment; therefore, it remains unclear if, and to what extent, the observed differences reflect the heterogeneous pharmacological properties of each compound. To help clarify the evidence, in this systematic review we investigated differences in trial characteristics which may have had an impact on the primary and secondary trial results, including baseline control of risk factors, prevalence of cardiovascular diseases, absolute rates of events, duration of the study, and definitions of the inclusion criteria and outcomes. Aiming at enhancing the clinical interpretation of these CVOTs, we quantified the absolute treatment effect over time in terms of the number needed to treat to avoid one major adverse cardiovascular event, showing variations among GLP-1RAs.