More than a decade after an FDA mandate for cardiovascular outcomes trials, cardiologists say insights gained on how 2 new drug classes affect heart failure in diabetes should be used to prevent complications. Several sessions at the 68th Scientific Session of the American College of Cardiology addressed this topic.
A decade ago, heart failure specialists were frustrated that the new wave of outcomes trials in diabetes would focus on easily seen events, like heart attacks and strokes, and not on the silent march of this chronic condition that leaves patients fatigued and at risk for kidney failure or liver damage.
It’s a different story this year at the American College of Cardiology’s 68th Scientific Sessions. Make no mistake: heart failure in diabetes has arrived. The meeting has seen results from a large clinical trial, daily sessions on heart failure and diabetes, and updated primary prevention guidelines that boost 2 drug classes shown to reduce heart failure hospitalization.
Driving this is the ACC’s new Expert Consensus Decision Pathway on Novel Therapies for Cardiovascular Risk Reduction in Patients With Type 2 Diabetes and Atherosclerotic Disease. Published November 30, 2018, the document represents a bolder step by cardiologists into diabetes care and the fruits of stronger collaboration with the American Diabetes Association. The 2 groups cross endorsed key guidelines in the past year, including the pathway.
At a Saturday session, “The Intersection of Heart Failure and Diabetes,” Mikhail Kosiborod, MD, professor of medicine at St. Luke’s Mid America Heart Institute, outlined the physical risk factors in diabetes that give rise to heart failure, and account for its increased prevalence. It’s not just that diabetes is a risk factor; the condition causes structural abnormalities cause heart failure to become worse.
Rising obesity rates (and resulting insulin resistance) along with an aging population mean the numbers will likely get worse. Anita Deswal, MD, MPH, FACC, professor of medicine, Baylor College of Medicine, noted that insulin resistance is present in 60% of heart failure patients, and that people with diagnosed T2D account for more than 40% of those in recent acute heart failure trials. What’s more, diabetes in heart failure is deadly: patients with diabetes were more than twice as likely to die in a 2015 study (Cavender et al., Circulation) that Deswal cited.
The only path forward, cardiologist said throughout the meeting, is prevention. And managing blood sugar is not enough.
In “Changing the Paradigm in Cardiovascular Risk Reduction in Diabetes,” Jim Januzzi, MD, of Massachusetts General Hospital substituted for Kosiborod’s presentation on the new ACC Decision Pathway, which calls on cardiologists to play a greater role in managing T2D.
The arrival of sodium glucose co-transporter 2 (SGLT2) inhibitors and glucagon-like peptide-1 (GLP-1) receptor agonists could mean that early intervention will forestall heart failure and renal problems, based on evidence seen in a series of cardiovascular outcomes trials. More trials specifically dedicated to SGLT2 inhibitors in heart failure (even for people without diabetes) and in renal function are yielding results. For cardiologists, this brings opportunities and a few challenges:
- Keeping up with the studies and rapid changes in the field is challenging.
- Some recommendations may conflict, and cardiologists have to reconcile their role with that of the endocrinologist or the primary care physician.
- New drugs that bring the most benefits may have side effects or cost more than patients will be willing to pay, especially if the drugs are not on formulary.
As Januzzi explained, however, the cardiologist can find their role by taking a broader view. “We really should be thinking of the non-glucocentric view. Management of diabetes is important—and so is reducing cardiovascular risk in these patients.”
Kosiborod said that, in order to encourage adherence, it’s essential to explain to patients what each drug does and why they are taking it. “You’d be surprised to know how many have no idea why they are taking it,” he said.
The panel included several fellows in training who presented case studies, and audience members voted on whether an SGLT2 inhibitor or a GLP-1 receptor agonist was more appropriate, given the patient’s preferences, symptoms, and other factors. A GLP-1 receptor agonist may bring greater weight loss, but some patients cannot accept an injectable drug. Patients who have had genital area infections may want to move away from an SGLT2 inhibitor, as this is a common side effect. Some scenarios examined when physicians could drop a loop diuretic, because the new classes can reduce hypertension.
Then came the question: is metformin, typically the first diabetes medication prescribed, always necessary with these new treatments? The panel was divided; Kosiborod said he wasn’t convinced that metformin was always necessary, while others said they’d like to see data before making a decision. It turns out data are on the way—Kosiborod said a Veterans Health Administration study on metformin will be coming in a few years.