Long-term patiromer adherence and renin-angiotensin aldosterone system inhibitor utilization: A retrospective study

BACKGROUND: Renin-angiotensin aldosterone system inhibitors (RAASi) reduce mortality risk in patients with heart failure, and slow progression of chronic kidney disease. However, hyperkalemia limits initiation, continuation, and reaching adequate dosing of RAASi therapy. Randomized trials have shown that patiromer users are more likely to continue taking RAASi. AIM: To test the hypothesis of whether patiromer facilitates optimal RAASi use in the real-world. METHODS: This study compared RAASi use in patients adherent with patiromer [proportion of days covered (PDC) > 80%] to patients with lower adherence (PDC ≤ 80%). Pre-pandemic (2014 to 2019) prescription claims data, member demographics, and plan information were used for individuals whose first patiromer prescription (index date) was during 2015-2018. PDC for patiromer was measured 6 months post-index. Patients were divided into two cohorts: Those with patiromer PDC > 80% (adherent) and those with patiromer PDC ≤ 80% (lower adherence). RAASi use was compared between cohorts during the 6 months post-index period. RESULTS: Nearly 25% of all patiromer users were adherent, with a patiromer PDC > 80%. Adherent patiromer use was associated with significantly more angiotensin-converting enzyme inhibitor, angiotensin-receptor blocker, and mineralocorticoid receptor antagonist days supply than lower patiromer adherence (10%, 8%, and 9% higher, respectively). Also, angiotensin-converting enzyme inhibitor, angiotensin-receptor blocker, and mineralocorticoid receptor antagonist PDC were significantly greater in adherent patiromer patients than in lower adherence patiromer patients (5%, 6%, and 10% higher, respectively). CONCLUSION: This study provides evidence that patients adherent with patiromer use more RAASi than lower-adherence patients. Prior studies show RAASi use reduces mortality risk and kidney disease progression.