STOCKHOLM – Recent study results confirm that two agents from the sodium-glucose cotransporter 2 (SGLT2) inhibitor class can significantly cut the incidence of adverse cardiovascular events in patients with heart failure with reduced ejection fraction (HFpEF), a disease especially common in people with type 2 diabetes, obesity, or both.
And findings from secondary analyses of the studies – including one reported at the annual meeting of the European Association for the Study of Diabetes – show that these SGLT2 inhibitors work as well for cutting incident adverse events (cardiovascular death or worsening heart failure) in patients with HFpEF and diabetes as they do for people with normal blood glucose levels.
But delivering treatment with these proven agents, dapagliflozin (Farxiga) and empagliflozin (Jardiance), first requires diagnosis of HFpEF, a task that clinicians have historically fallen short in accomplishing.
When in 2021, results from the EMPEROR-Preserved trial with empagliflozin and when in September 2022 results from the DELIVER trial with dapagliflozin established the efficacy of these two SGLT2 inhibitors as the first treatments proven to benefit patients with HFpEF, they also raised the stakes for clinicians to be much more diligent and systematic in evaluating people at high risk for developing HFpEF because of having type 2 diabetes or obesity, two of the most potent risk factors for this form of heart failure.
‘Vigilance ... needs to increase’
“Vigilance for HFpEF needs to increase because we can now help these patients,” declared Lars H. Lund, MD, PhD, speaking at the meeting. “Type 2 diabetes dramatically increases the incidence of HFpEF,” and the mechanisms by which it does this are “especially amenable to treatment with SGLT2 inhibitors,” said Dr. Lund, a cardiologist and heart failure specialist at the Karolinska Institute, Stockholm.
HFpEF has a history of going undetected in people with type 2 diabetes, an ironic situation given its high incidence as well as the elevated rate of adverse cardiovascular events when heart failure occurs in patients with type 2 diabetes compared with patients who do not have diabetes.
The key, say experts, is for clinicians to maintain a high index of suspicion for signs and symptoms of heart failure in people with type 2 diabetes and to regularly assess them, starting with just a few simple questions that probe for the presence of dyspnea, exertional fatigue, or both, an approach not widely employed up to now.
Clinicians who care for people with type 2 diabetes must become “alert to thinking about heart failure and alert to asking questions about signs and symptoms” that flag the presence of HFpEF, advised Naveed Sattar, MBChB, PhD, a professor of metabolic medicine at the University of Glasgow.
Soon, medical groups will issue guidelines for appropriate assessment for the presence of HFpEF in people with type 2 diabetes, Dr. Sattar predicted in an interview.
A need to probe
“You can’t simply ask patients with type 2 diabetes whether they have shortness of breath or exertional fatigue and stop there,” because often their first response will be no.
“Commonly, patients will initially say they have no dyspnea, but when you probe further, you find symptoms,” noted Mikhail N. Kosiborod, MD, codirector of Saint Luke’s Cardiometabolic Center of Excellence in Kansas City, Mo.
These people are often sedentary, so they frequently don’t experience shortness of breath at baseline, Dr. Kosiborod said in an interview. In some cases, they may limit their activity because of their exertional intolerance.
Once a person’s suggestive symptoms become known, the next step is to measure the serum level of N-terminal pro-B-type natriuretic peptide (NT-proBNP), a biomarker considered to be a generally reliable signal of existing heart failure when elevated.
Any value above 125 pg/mL is suggestive of prevalent heart failure and should lead to the next diagnostic step of echocardiography, Dr. Sattar said.
Elevated NT-proBNP has such good positive predictive value for identifying heart failure that it is tempting to use it broadly in people with type 2 diabetes. A 2022 consensus report from the American Diabetes Association says that “measurement of a natriuretic peptide [such as NT-proBNP] or high-sensitivity cardiac troponin is recommended on at least a yearly basis to identify the earliest HF [heart failure] stages and implement strategies to prevent transition to symptomatic HF.”
Test costs require targeting
But because of the relatively high current price for an NT-proBNP test, the cost-benefit ratio for widespread annual testing of all people with type 2 diabetes would be poor, some experts caution.
“Screening everyone may not be the right answer. Hundreds of millions of people worldwide” have type 2 diabetes. “You first need to target evaluation to people with symptoms,” advised Dr. Kosiborod.
He also warned that a low NT-proBNP level does not always rule out HFpEF, especially among people with type 2 diabetes who also have overweight or obesity, because NT-proBNP levels can be “artificially low” in people with obesity.
Other potential aids to diagnosis are assessment scores that researchers have developed, such as the H2FPEF score, which relies on variables that include age, obesity, and the presence of atrial fibrillation and hypertension.
However, this score also requires an echocardiography examination, another test that would have a questionable cost-benefit ratio if performed widely for patients with type 2 diabetes without targeting, Dr. Kosiborod said.
SGLT2 inhibitors benefit HFpEF regardless of glucose levels
A prespecified analysis of the DELIVER results that divided the study cohort on the basis of their glycemic status proved the efficacy of the SGLT2 inhibitor dapagliflozin for patients with HFpEF regardless of whether or not they had type 2 diabetes, prediabetes, or were normoglycemic at entry into the study, Silvio E. Inzucchi, MD, reported at the EASD meeting.
Mitchel L. Zoler/MDedge News
Dr. Silvio E. Inzucchi
Treatment with dapagliflozin cut the incidence of the trial’s primary outcome of cardiovascular death or worsening heart failure by a significant 18% relative to placebo among all enrolled patients.
The new analysis reported by Dr. Inzucchi showed that treatment was associated with a 23% relative risk reduction among those with normoglycemia, a 13% reduction among those with prediabetes, and a 19% reduction among those with type 2 diabetes, with no signal of a significant difference among the three subgroups.
“There was no statistical interaction between categorical glycemic subgrouping and dapagliflozin’s treatment effect,” concluded Dr. Inzucchi, director of the Yale Medicine Diabetes Center, New Haven, Conn.
He also reported that, among the 6,259 people in the trial with HFpEF, 50% had diabetes, 31% had prediabetes, and a scant 19% had normoglycemia. The finding highlights once again the high prevalence of dysglycemia among people with HFpEF.
Previously, a prespecified secondary analysis of data from the EMPEROR-Preserved trial yielded similar findings for empagliflozin that showed the agent’s efficacy for people with HFpEF across the range of glucose levels.
The DELIVER trial was funded by AstraZeneca, the company that markets dapagliflozin (Farxiga). The EMPEROR-Preserved trial was sponsored by Boehringer Ingelheim and Eli Lilly, the companies that jointly market empagliflozin (Jardiance). Dr. Lund has been a consultant to AstraZeneca and Boehringer Ingelheim and to numerous other companies, and he is a stockholder in AnaCardio. Dr. Sattar has been a consultant to and has received research support from AstraZeneca and Boehringer Ingelheim, and he has been a consultant with numerous companies. Dr. Kosiborod has been a consultant to and has received research funding from AstraZeneca and Boehringer Ingelheim and has been a consultant to Eli Lilly and numerous other companies. Dr. Inzucchi has been a consultant to, given talks on behalf of, or served on trial committees for Abbott, AstraZeneca, Boehringer Ingelheim, Esperion, Lexicon, Merck, Novo Nordisk, Pfizer, and vTv Therapetics.
A version of this article first appeared on Medscape.com.