Introduction: Heart failure (HF) and reduced ejection fraction (HFrEF) requires timely ACC/AHA guideline recommended treatment (Tx) with multiple pharmacotherapies, including renin-angiotensin system and sympathetic nervous system blockers. The relationship between initial pharmacotherapies (IPT) and treatment modifications ([TM]: add-on or switch to a new class, or discontinuation of IPT) in real world practice is not well understood.
Methods: This retrospective cohort study identified Humana Medicare managed care patients (pts) with ≥2 claims for HF from 8/2010-7/2015. The 1st HF claim was the index date. Patients had 1-year (yr) continuous enrollment, no HF diagnosis prior to index, and continuous enrollment 2-yrs post-index or until death. A claims-based algorithm was used to derive HFrEF status. IPT were mono- or combo-use of ACE-inhibitor (ACEI), angiotensin II receptor blocker (ARB), beta blocker (BB), hydralazine-nitrate (HN), and aldosterone antagonist (AA) in 1 yr post-index. No IPT was no drug use, only 1 fill, or <28-day supply in the 1st yr. Time from IPT to 1st TM in 2 yrs post-index and subsequent therapies were identified.
Results: Of 14,359 HFrEF pts, mean (SD) age was 75 (±8) yrs; 45% were female. Post-index, 32% had no IPT after 1 yr, 61% had IPT within 1 month, and 7% initiated IPT after the 1st month. Of pts with IPT (n=9705), 48% received mono vasodilators (ACEI/ARB or HN), 17% mono BB, 23% vasodilator+BB, and 4% triple therapy [(ACEI/ARB)+BB+(HN or AA)]. Among pts on IPT, 52% had 1st TM within 2 yrs post-index, with 26% adding a new class, 7% switching to a new class, 9% discontinuing a class of IPT, and 9% discontinuing all IPT. Mean (SD) time from IPT to 1st TM was 9 (±7) months. For pts with subsequent therapies after 1st TM, vasodilator+BB was most common (41%), followed by mono vasodilator (15%); then triple therapy (12%). (Table 1)
Conclusion: Despite national HFrEF Tx guidelines recommending combo use of vasodilator+BB, nearly 1/3 of pts had no IPT within 1 yr post-index and over ½ received mono Tx as IPT. Of pts on IPT, mean time to 1st TM was 9 months and few initiated triple therapy. In clinical trials, dual (vasodilator+BB) or triple therapies improved health outcomes. Consequences of HF pharmacotherapy gaps warrant further study.