Table 3.
Deterministic sensitivity analyses
| Parameter | Base case | Sensitivity analysis |
|---|---|---|
| Time horizon | 3 years | 1,5 and 10 years and lifetime (25 years) time horizons |
| Discount rate | 3% | 0% and 5% |
| Patient population and utility estimation | Equation developed in the previous cost-effectiveness analysis [26], based on an observational Spanish study [39] | Base case population with utilities estimated from GALAXY utility algorithm ITT study population with utilities estimated from GALAXY utility algorithm ITT study population with utilities estimated from GALAXY utility algorithm over a lifetime horizon |
| FEV1 treatment effect | UMEC/VI 180 mL, TIO/OLO 128 mL (incremental FEV1 treatment effect of 52 mL (favoring UMEC/VI) | Equal FEV1 treatment effect (128 mL) for UMEC/VI and TIO/OLO Incremental FEV1 treatment effect with UMEC/VI equal to the upper (+ 77 mL) and lower (+ 28 mL) 95% CI |
| Treatment discontinuation | 8.7% | 50% for year 1 (from population-based, retrospective, observational study in Catalonia [55]) and 8.7% (from the UPLIFT trial [41]) for subsequent years |
| Subsequent treatment | SAL/FP 50/500 mcg, two inhalations per day + TIO 18 mcg | Patients on UMEC/VI add FP 500 mcg, two inhalations per day; patients on TIO/OLO escalate to SAL/FP 500/50 mcg, two inhalations per day + TIO 18 mcg, one inhalation per daya |
| Costing for dyspneab | €524.87/year; €699.98/year; €925.85/year |
Cost of level of dyspnea ±20% |
| Costing for exacerbationsb | Moderate €72.76c; severe €4466.09d | Cost of exacerbations ±20% |
CI confidence interval, ED emergency department, FEV1 forced expiratory volume in one second, FP fluticasone propionate, ITT intent-to-treat, OCS oral corticosteroid, SAL salmeterol xinafoate, TIO/OLO tiotropium/olodaterol, UMEC/VI umeclidinium vilanterol, UPLIFT Understanding Potential Long-Term Impacts on Function with Tiotropium
aThis sensitivity analysis assumed that patients in both the UMEC/VI and TIO/OLO arms experienced the same FEV1 improvement upon escalating to triple therapy (assumed to be + 52 mL)
binflated to 2017 Euros using the Consumer Price Index [38]
ccost of OCS and/or antibiotics, one primary care visit and one ED visit for 4.3% patients
dcost of one primary care visit, one ED visit, and hospitalization for 8 days