Cost-effectiveness of screening for carotid stenosis in asymptomatic persons.
BACKGROUND
The Asymptomatic Carotid Atherosclerosis Study (ACAS) showed that carotid endarterectomy was beneficial for symptom-free patients with carotid stenosis of 60% or more. This finding raises the question of whether widespread screening to identify cases of asymptomatic carotid stenosis should be implemented.


OBJECTIVE
To determine whether a screening program to identify cases of asymptomatic carotid stenosis would be a cost-effective strategy for stroke prevention.


METHODS
Cost-effectiveness analysis using published data from clinical trials.


METHODS
General population of asymptomatic 65-year-old men.


METHODS
Patients who were screened for carotid disease with duplex Doppler ultrasonography were compared with patients who were not screened. If ultrasonography found significant carotid stenosis (> or = 60%), disease was confirmed by angiography before carotid endarterectomy was done.


METHODS
Quality-adjusted life-years, costs, and marginal cost-effectiveness ratios.


RESULTS
When the conditions and results of ACAS were modeled and it was assumed that the survival advantage produced by endarterectomy would last for 30 years, the lifetime marginal cost-effectiveness of screening relative to no screening was $120,000 per quality-adjusted life-year. Sensitivity analysis showed that marginal cost-effectiveness decreased to $50,000 or less per quality-adjusted life-year only under implausible conditions (for example, if a free screening instrument with perfect test characteristics was used or an asymptomatic population with a 40% prevalence of carotid stenosis was found).


CONCLUSIONS
Surgery offers a real but modest absolute reduction in the rate of stroke at a substantial cost. A program to identify candidates for endarterectomy by screening asymptomatic populations for carotid stenosis costs more per quality-adjusted life-year than is usually considered acceptable.
Lee
T T
TT
Kaiser Permanente, Oakland, CA 94612, USA.
Solomon
N A
NA
Heidenreich
P A
PA
Oehlert
J
J
Garber
A M
AM
D000368:Aged; D016893:Carotid Stenosis / Q000000981:diagnostic imaging* / Q000601:surgery; D002561:Cerebrovascular Disorders / Q000517:prevention & control*; D003362:Cost-Benefit Analysis; D003661:Decision Support Techniques; D016894:Endarterectomy, Carotid; D017048:Health Care Costs; D006801:Humans; D008297:Male; D008403:Mass Screening / Q000191:economics*; D019057:Quality-Adjusted Life Years; D012680:Sensitivity and Specificity; D018616:Ultrasonography, Doppler, Duplex / Q000191:economics