Context In the Treat Angina with Aggrastat and Determine Cost of Therapy with
an Invasive or Conservative Strategy (TACTICS)–Thrombolysis in Myocardial
Infarction (TIMI) 18 trial, patients with either unstable angina or non–ST-segment
elevation myocardial infarction (UA/NSTEMI) treated with the platelet glycoprotein
(Gp IIb/IIIa) inhibitor tirofiban had a significantly reduced rate of major
cardiac events at 6 months with an early invasive vs a conservative strategy.
Objective To examine total 6-month costs and long-term cost-effectiveness of an
invasive vs a conservative strategy.
Design Randomized controlled trial including a priori economic end points.
Setting Hospitalization for UA/NSTEMI with 6-month follow-up period.
Patients A total of 2220 patients with UA/NSTEMI; economic data from 1722 patients
at US–non-VA hospitals.
Intervention Early invasive strategy with routine catheterization and revascularization
as appropriate vs a conservative strategy with catheterization performed only
for recurrent ischemia or a positive stress test.
Main Outcome Measure Total 6-month costs and incremental cost-effectiveness ratio.
Results The average initial hospitalization costs among those in the invasive
strategy group were $15714 vs $14047 among those in the conservative stategy
group, a difference of $1667 (95% confidence interval [CI], $387-3091). The
in-hospital costs were offset significantly at the 6-month follow-up, with
an average cost in the invasive group of $6098 vs $7180 in the conservative
group, a difference of $1082 (95% CI, −$2051 to $76). The average total
costs at 6 months, including productivity costs, for the invasive group was
$21 813 vs $21 227 for the conservative group, a $586 difference
(95% CI, −$1087 to $2486). The average 6-month costs excluding productivity
costs in the invasive group was $19 780 vs $19 111 in the conservative
group, a difference of $670, 95% CI; (−$1035 to $2321). Estimated cost
per year of life gained for the invasive strategy, based on projected life
expectancy, was $12739 for the base case, and ranged from $8371 to $25769,
based on model assumptions.
Conclusions In patients with UA/NSTEMI treated with the Gp IIb/IIIa inhibitor tirofiban,
the clinical benefit of an early invasive strategy was achieved with a small
increase in cost, yielding favorable projected estimates of cost per year
of life gained. These results support the broader use of an early invasive
strategy in these patients.