Type 2 diabetes and cardiovascular prevention: the dogmas disputed

Dario Giugliano, Maria Ida Maiorino, Giuseppe Bellastella, Katherine Esposito

In randomized controlled trials (RCTs), more intensive glucose control in patients with type 2 diabetes leads to a modest (9%) reduction in major cardiovascular events (MACE), associated with a 20% reduction of kidney events and 13% reduction of eye events. The FDA issued guidance in 2008 led to the conduct of numerous cardiovascular outcomes (CVOT) trials to assess cardiovascular safety of new antihyperglycemic therapies in patients with type 2 diabetes. The results of these trials show that insulin glargine, three different dipeptidyl peptidase-4 (DPP-4) inhibitors (saxagliptin, alogliptin, and sitagliptin) and lixisenatide (a glucagon like peptide-1 receptor agonist) produce no significant difference in CVOT when compared with usual care or placebo. Other trials with newer diabetes drugs, including empagliflozin and canagliflozin (two sodium-glucose co-transporter-2 inhibitors), liraglutide and semaglutide (two GLP-1 receptor agonists) succeeded in demonstrating CV benefit in people with type 2 diabetes. In the last two decades, the equation "diabetes equals myocardial infarction" have contributed to the development of preventive therapy for risk factors in diabetes. In both primary and secondary prevention, the diabetic patients with high rates of statin and aspirin treatment have improved CV outcome, as compared with non-users. The drugs used to reduce glucose levels in patients with type 2 diabetes seem important for the ultimate cardiovascular outcome: the combination of intensive glycemic control, when safely attainable, with newer diabetes drugs (empagliflozin, canagliflozin, liraglutide, and semaglutide) may decrease the incidence of MACE, nephropathy and retinopathy. Moreover, depending on the drug used, CV mortality and heart failure may also be reduced.