Obstacles to mineralocorticoid receptor antagonists in a community-based heart failure population

Previous studies and national assessments indicate an undertreatment of mineralocorticoid receptor antagonists (MRA) in heart failure with reduced ejection fraction (HFrEF). This study aimed to investigate why MRA is not used to full extent.

A complete community-based heart failure population was studied. Several variables were collected, and medical records were scrutinized to identify reasons for not prescribing MRA.

Of 2029 patients, 812 had EF ≤40%. Five hundred and fifty-three patients (68%) tried MRA at some point but 184 of these (33%) discontinued therapy. There were 259 patients that never tried MRA with 177 with a listed explanation or contraindication. Eighty-two patients, 10% of the total HFrEF population, had no clear contraindications. They were older and had less HF hospitalizations compared to patients on MRA (P < 0.05) and 32% did not have any follow-up at the cardiology clinic. Contraindications to MRA were renal dysfunction (93 patients), hypotension (28 patients), and hyperkalemia (25 patients). Only six patients had hyperkalemia without renal dysfunction. Of the patients with renal dysfunction, 66 (72%) had eGFR >30 mL/min.

The reasons why MRA are underutilized were mainly because of contraindications. However, the data suggest that physicians are overly cautious about moderately reduced kidney function. There seems to be a 10%-18% avoidable undertreatment with MRA, especially for elderly patients that are admitted to the hospital for other reasons than heart failure. This suggests that patients with heart failure would benefit from routine follow-up at a cardiology clinic.