Out-of-pocket payments for part d covered medications by medicare fee-for-service beneficiaries with heart failure with reduced ejection fraction

BACKGROUND: Out-of-pocket (OOP) drug costs for Medicare Fee-for-Service (FFS) beneficiaries with heart failure with reduced ejection fraction (HFrEF) are not well characterized. This study evaluated Part D OOP spending by Medicare beneficiaries with chronic HFrEF, stratified by those with and without a worsening HF event (WHFE). METHODS: Medicare FFS 100% Part D claims were used to identify HFrEF patients with 12 months of continuous Part D enrollment in 2018. HFrEF was defined as 1 inpatient or 2 outpatient claims of systolic HF or 1 systolic HF plus 1 HF outpatient claim. WHFE was defined as having a HF hospitalization or intravenous diuretic use within 12 months of HFrEF index date. OOP costs by Medicare Part D coverage phase for all covered drugs were calculated for HFrEF patients, and those with and without WHFE. RESULTS: Of 305,373 Medicare patients with HFrEF, 26% had a WHFE. Total mean (SD) OOP drug costs among all HFrEF patients was $1,166 (1,205)/year. Patients with WHFE and patients without WHFE had respectively a mean (SD) annual OOP costs of $1,302 (1,273) and $1,117 (1,176). Over 39% of HFrEF patients entered the "donut hole" (44% and 37% of patients with WHFE and without WHFE, respectively), while 11% of HFrEF patients entered the catastrophic phase (13% and 10% of patients with and without WHFE, respectively). CONCLUSIONS: More than 1 in 10 patients with heart failure entered the catastrophic phase within Medicare-Fee-For-Service, whereas in 2018 only 10% of costs were attributable to heart failure medication and 90% to comorbidities.