Which New Drug Class Is Best for Heart Protection in Type 2 Diabetes?

Sara Freeman

September 28, 2021

When it comes to protecting diabetic hearts, sodium-glucose cotransporter-2 (SGLT2) inhibitors may have a slight edge over glucagonlike peptide-1 receptor agonists (GLP-1 RAs) according to the results of large, population-based, observational cohort study.

Around a 30% reduction in the risk for being hospitalized for heart failure was achieved in people with type 2 diabetes who were treated with an SGLT2 inhibitor over a GLP-1 RA regardless of whether the patients had a preexisting heart condition.

The findings, published in the Annals of Internal Medicine, also showed a 10% lower risk for myocardial infarction or stroke among those treated with an SGLT2 inhibitor who had preexisting cardiovascular disease (CVD), although there was no difference in risk between the two classes of drugs in those without preexisting CVD.

"These findings are important as they suggest that SGLT2 [inhibitors] and GLP-1 RA offer similar benefits in preventing myocardial infarction and stroke in patients with diabetes," said study investigator Elisabetta Patorno, MD, DrPH, of Brigham and Women's Hospital and Harvard Medical School in Boston, in an interview.

They also show "that SGLT2 [inhibitors] offer greater efficacy in preventing heart failure, which supports the existing guidelines," she added.

Paul S. Jellinger, MD, MACE, of the Center for Diabetes and Endocrine Care, Hollywood, Fla., said these data were likely to be "additive to guidelines but not transformative." The overall analysis results were "not surprising." It was not unexpected that SGLT2 inhibitors provided a robust chronic heart failure (CHF) benefit in individuals with history of CVD, he said.

Jellinger, a clinical endocrinologist and professor of clinical medicine at the University of Miami, observed, however, that "the similar CVD benefit in both drug classes in patients without known CVD adds to our knowledge in this somewhat controversial area and may be useful to the clinician in evaluating therapy in a diabetic individual without evidence of or at high risk for CHF."

Furthermore, "the study also reminds us that, as demonstrated in published meta-analysis, there is also a modest CHF benefit associated with GLP-1 RA treatment particularly in patients with a history of CVD."

Addressing the Knowledge Gap

Thanks to the results of many large-scale, prospective, cardiovascular outcomes studies, both SGLT2 inhibitors and GLP1 RA have been recommended as treatment for people with diabetes who have established CVD. But with no direct head-to-head trials having been conducted, there is a gap in knowledge and there is currently little guidance for physicians on which drug class to choose for an individual patient.

To try to clarify things, Patorno and associates looked at data from more than 370,000 people with type 2 diabetes who had been treated between April 2013 and December 2017 with either an SGLT2 inhibitor (canagliflozin, dapagliflozin, or empagliflozin) or GLP-1 RA (albiglutide, dulaglutide, exenatide, or liraglutide).

One-to-one propensity score matching was used to create the study groups: participants were first grouped according to their history of CVD, and then by the class of drug they had been prescribed. The primary outcomes were hospitalization for MI, stroke, or heart failure.

Comparing the initiation of an SGLT2 inhibitor with GLP-1 RA therapy, the hazard ratios (HRs) for MI or stroke in patients with and without a history of CVD were a respective 0.90 (95% CI, 0.82 to 0.98) and 1.07 (0.97 to 1.18).

The corresponding hazard ratios for heart failure hospitalizations were 0.71 (0.64 to 0.79) and 0.69 (0.56 to 0.85).

Real-World Studies Are of 'Increasing Value'

"As in other not-randomized studies based on real-world data, residual confounding cannot be completely ruled out," Patorno acknowledged. She added, however that "state-of-the-art methodological strategies were implemented to minimize this possibility."

Limitations notwithstanding, "real world studies are demonstrating increasing value," observed Jellinger. Further large-scale cardiovascular outcomes trials that directly compare these two drug classes "are unlikely given the depth of information available now," Jellinger suggested.

"This head-to-head retrospective study may be as close as we get and does represent the first effort at a comparison of these two classes."

Patorno said of the potential clinical implications: "Because the two classes are equally effective for stroke and myocardial infarction, but the SGLT2 inhibitors are superior for heart failure, when considered in aggregate, SGLT2 inhibitors are likely to prevent more of these adverse cardiovascular events than GLP-1 RA."

The study received no commercial funding and was supported by the Brigham and Women's Hospital and Harvard Medical School Division of Pharmacoepidemiology and Pharmacoeconomics.

Patorno and Jellinger reported no conflicts of interest.

This article originally appeared on MDedge.com, part of the Medscape Professional Network.


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