Yes, Clinical Inertia IS the Leading Cause of GDMT Underuse in HFrEF

Heart failure specialists finally have data to back up their long-standing suspicions that clinical inertia is to blame for the underuse of the four-pillar treatment approach for patients who have heart failure with reduced ejection fraction (HFrEF). According to a survey of primary care physicians and cardiologists, the number one reason for not prescribing quadruple guideline-directed medical therapy (GDMT) was that they felt patients’ current medications were sufficient.

Overall, 85.4% of patients seen by these physicians were not prescribed quadruple therapy that included an ACE inhibitor/ARB/angiotensin receptor-neprilysin inhibitor (ARNI), a beta-blocker, a mineralocorticoid receptor antagonist (MRA), and a sodium-glucose cotransporter 2 (SGLT2) inhibitor.

When asked why their patients weren’t taking the four pillars of GDMT, doctors most frequently said that they were “clinically stable and/or had adequate symptom control” without a particular drug (in 43% to 55% of cases depending on the specific class of medications) as the primary reason, Stephen Greene, MD (Duke Clinical Research Institute, Durham, NC), and colleagues report in a research letter published online Wednesday in JACC: Heart Failure.

Other reasons, including patient preference, high out-of-pocket cost, low blood pressure, a previously proven intolerance, kidney dysfunction, and hyperkalemia, were much less common.

There have been multiple studies demonstrating gaps in the use of GDMT for HFrEF in clinical practice, “so it's not new that these medications are prescribed at low rates, unfortunately,” Greene told TCTMD. “But the question is why, and we debate almost endlessly about why these different gaps in GDMT exist.”

In that context, these findings “really are the first data in real-world clinical practice that I'm aware of where clinicians are directly admitting that they do not believe that GDMT is necessary for patients with HFrEF,” he said.

“It's directly contrary to class 1 guideline recommendations and really inconsistent with data suggesting that even patients that are ‘stable’ with their HFrEF [still have] an extreme-risk condition,” he continued. “It shows that clinicians are, generally speaking, in this sample underappreciating the risk that we're dealing with, with HFrEF, and misinterpreting what guidelines are saying and what the evidence supports.”

For the study, the investigators examined data from the Adelphi Real World Heart Failure Disease Specific Programme, a cross-sectional survey of cardiologists and primary care physicians in the United States that included retrospective data collection between August 2022 and February 2023. Physicians were asked to audit their records and choose the primary reason for not prescribing various components of GDMT for their patients with HFrEF seen in outpatient clinics.

The study included responses from 53 cardiologists and 33 primary care physicians, covering a total of 323 patients with HFrEF (median age 67 years; 39% women). About half of patients were covered by Medicare (50.2%), 36.5% by commercial insurance, 7.4% by Medicaid, and 2.5% by Veterans Affairs benefits.

The idea that someone has mild symptoms at a given point in time or is perceived as stable: that is not a valid excuse for not initiating GDMT in a patient who is otherwise eligible. Stephen Greene

The likelihood that a patient was not on all four components of GDMT was higher for those seen by a primary care physician versus a cardiologist (91.2% vs 82.4%; P = 0.046). Patients managed in primary care were more likely to not get a beta-blocker (23.0% vs 12.9%; P = 0.027), although care setting didn’t influence the likelihood of getting the other classes of medications.

Overall, the rate of nonprescription ranged from a low of 16.4% for beta-blockers to a high of 84% for ARBs, with intermediate rates for ARNIs (57%), ACE inhibitors (62%), SGLT2 inhibitors (65%), and MRAs (72%).

Believing a patient to be clinically stable and/or having adequate symptom control on existing medications was the leading reason for not prescribing the various drugs. Physicians were less likely to point to patient preference (7% to 13% of cases), high cost or insurance coverage (2% to 14%), previously proven intolerance (1% to 9%), low blood pressure (7% to 10%), kidney dysfunction (0 to 9%), current or recent hyperkalemia (0 to 4%), and “other” (4% to 25%). The last category included factors like polypharmacy and comorbidities.

The distribution of the various reasons did not significantly differ between primary care physicians and cardiologists.

No Excuses

To remedy the underuse of GDMT, “we really need further initiatives to urgently educate physicians regarding the importance of rapidly initiating GDMT to all our eligible patients with HFrEF,” Greene said. “The idea that someone has mild symptoms at a given point in time or is perceived as stable: that is not a valid excuse for not initiating GDMT in a patient who is otherwise eligible.”

Greene underscored the importance of the issue by noting that the prognosis for many patients with heart failure is comparable to that seen for patients with many forms of cancer. “In cancer, we have a culture of therapeutic urgency, whereas in heart failure, we have a culture of therapeutic hesitancy, or just risk is underappreciated, and we essentially waste time and then patients unfortunately don't get the opportunity to benefit from therapies proven to help them. And then we get preventable deaths and hospitalizations.”

He stressed: “Urgent education is needed.”