Background: Fixed-dose combination of isosorbide dinitrate/hydralazine (ISDN/HYD) improved clinical outcomes in the African-American Heart Failure Trial (A-HeFT). We assessed the resource use, costs of care, and cost-effectiveness of ISDN/HYD therapy in the A-HeFT trial population.
Methods and results: We obtained resource use data from A-HeFT, assigning costs through the use of US federal sources. Excluding indirect costs, we summarized the within-trial experience and modeled cost-effectiveness over extended time horizons, including a US societal lifetime reference case. During the mean trial follow-up of 12.8 months, the ISDN/HYD group incurred fewer heart failure-related hospitalizations (0.33 versus 0.47 per subject; P=0.002) and shorter mean hospital stays (6.7 versus 7.9 days; P=0.006). When study drug costs were excluded, both heart failure-related and total healthcare costs were lower in the ISDN/HYD group (mean per-subject heart failure-related costs, 5997 dollars versus 9144 dollars; P=0.04; mean per-subject total healthcare costs, 15,384 dollars versus 19,728 dollars; P=0.03). With an average daily drug cost of 6.38 dollars, ISDN/HYD therapy was dominant (reduced costs and improved outcomes) over the trial duration. Assuming that no additional benefits accrue beyond the trial, we project the cost-effectiveness of ISDN/HYD therapy using heart failure-related costs to be 16,600 dollars/life-year at 2 years after enrollment, 37,100 dollars/life-year at 5 years, and 41,800 dollars/life-year over lifetime (reference case).
Conclusions: ISDN/HYD therapy, previously shown to improve clinical outcomes, also reduced resource use and costs in A-HeFT, primarily because of a large reduction in hospitalizations. Long-term use of ISDN/HYD therapy should be associated with a favorable cost-effectiveness profile in this population.