Changes in the use of carotid revascularization among the medicare population.

HYPOTHESIS: It remains unknown if the increasing use of carotid artery stenting (CAS) has caused a change in the population-based use of carotid endarterectomy (CEA). We sought to examine national trends in carotid revascularization.
DESIGN: Retrospective cohort study.
SETTING: Academic research. PATIENTS: All Medicare beneficiaries (MCBEs) between January 1, 1998, through December 31, 2004. MAIN OUTCOME MEASURES: We examined the frequency of CEA and CAS using Current Procedural Terminology codes for CEA, peripheral stent insertion, and cerebrovascular disease. To exclude patients who underwent stenting of a peripheral artery other than the carotid artery, we excluded all patients with a primary diagnostic code for peripheral vascular disease.
RESULTS: We identified 134 194 claims for carotid revascularization (9386 claims for CAS and 124 808 claims for CEA). The overall incidence of carotid revascularization procedures decreased slightly between 1998 and 2004, from 388.1 to 345.8 procedures per 100 000 MCBEs (11% decrease, P < .02). Between 1998 and 2004, the incidence of CEA decreased from 373.4 to 309.3 procedures per 100 000 MCBEs (17% decrease, P < .01), while the incidence of CAS increased from 14.6 to 36.4 procedures per 100 000 MCBEs (149% increase, P < .01).
CONCLUSIONS: While rates of carotid revascularization in the Medicare population slightly decreased between 1998 and 2004, the use of CAS dramatically increased. Whether this represents a substitution of CAS for CEA vs a broadening of indications for carotid revascularization using CAS is unknown but is of interest to patients and third-party payers and requires future investigation.