Cardiovascular risk associated with glucagon-like peptide-1 receptor agonists versus other conventional glucose-lowering drugs in patients with type-2 diabetes: protocol for a nationwide observational comparative study in routine care.

introductionSeveral cardiovascular outcome trials have been conducted to assess the cardiovascular safety and efficacy of glucagon-like peptide-1 receptor agonists (GLP1-RAs) on cardiorenal outcomes in patients with type-2 diabetes (T2D). However, the strict requirements of randomised controlled trials to avoid most confounding factors are at the expense of external validity. Using national real-world data, we aimed to evaluate the effectiveness of GLP-1RAs in association with metformin especially on cardiovascular events, hospitalisation for heart failure and all-cause death in comparison with other diabetes treatment schemes using dipeptidyl peptidase IV inhibitors, sulfonylureas/glinides or insulin also associated with metformin. Sodium-glucose transport protein 2 inhibitors (SGLT-2i) will be excluded as comparators, as this class of oral hypoglycaemic agents just started in 2020 to be marketed in France. METHODS AND ANALYSIS: The Système National des Données de Santé is a comprehensive nationwide administrative healthcare database in France that covers approximately 67 million people.Several cohorts of adult patients with T2D initiating any GLP1-RA in dual or triple therapies, as recommended by the French Health authorities, will be identified in this database over the period 2016-2021. These cohorts will be defined by the combination of glucose-lowering drugs prescribed simultaneously with GLP1-RA and diabetes treatment received over a 6-month period before GLP1-RA initiation. They will be first matched with T2D controls (1:3 ratio) based on the year of drug initiation and treatment regimens before and simultaneously with GLP1-RA in the different selected cohorts. Comparative analyses will be conducted versus these control groups, adjusting for cardiovascular event history and a propensity score considering age, sex, area of residence, deprivation index, comorbidities, duration of diabetes, use of lipid-lowering drugs, anticoagulants, antiplatelet therapies and blood pressure-lowering therapies. Comparative analyses will be conducted versus these control groups, using a high-dimensional propensity scores method and fixed baseline characteristics. Treatment effects on the different outcomes measured will be estimated for each GLP1-RA group, through HR and their corresponding CIs (95% CI) using Cox regressions and/or competitive risk regressions when necessary. ETHICS AND DISSEMINATION: The study has been approved by an independent ethics committee (Comité éthique et scientifique pour les recherches, les études et les évaluations dans le domaine de la santé, Paris, France; reference: 8699786, dated 2 June 2022) and has been registered with the French National Data Protection Commission (Commission Nationale de l'Informatique et des Libertés, Paris, France; reference: 922161, dated 26 June 2022). The findings of this study will be published in peer-reviewed scientific journals and presented at international conferences. TRIAL REGISTRATION NUMBER: F20220803152803.