Cardio-protective Effects of Glucagon-like Peptide-1 Receptor Agonists: An Overview of Systematic Reviews and Publication Overlap

Background: Glucagon-like peptide-1 receptor agonists (GLP-1RAs) have emerged as a new antihyperglycemic class with the demonstrated advantage of reducing major adverse cardiovascular events (MACE) among individuals with type 2 diabetes (T2DM), atherosclerotic cardiovascular disease, or high cardiovascular risk.

Objective: Τo summarize the evidence of systematic reviews (SRs) that assess MACE (cardiovascular mortality, nonfatal myocardial infarction, and stroke) and hospitalizations for heart failure in GLP-1RAs-treated patients and to evaluate possible overlap in pertinent SRs.

Methods: We performed a comprehensive search via MEDLINE, Cochrane Library, and PROSPERO databases up to February 23, 2020, for SRs examining cardiovascular outcomes of GLP-1RAs in T2DM patients. Three independent authors extracted data and assessed the methodological quality of the included SRs using the ROBIS tool.

Results: We found 37 SRs - published between 2009 and 2020 in English - of which 35 collected data only from randomized clinical trials while two from observational studies as well. The methodological quality of the 37 SRs ranged from low to high, while only 3 have evaluated the overall quality of evidence outcome using the Grading of Recommendations Assessments, Development and Evaluation (GRADE) approach. All the included SRs showed cardiovascular safety of GLP-1RAs while the latest ones demonstrated a reduction in composite MACE endpoint as well as its every individual component and heart failure hospitalizations.

Conclusion: In the first overview of SRs about cardiovascular outcomes of GLP-1RAs, they proved favorable effects on reducing cardiovascular events in T2DM patients. There are, however, many overlapping reviews based on relatively few cardiovascular outcomes trials.