Effect of the asymptomatic carotid atherosclerosis study on carotid endarterectomy in Florida

Abstract

Background and Purposes - The value of carotid endarterectomy (CEA) has been defined by several recent multicenter trials. The clinical effect of these trials remains undetermined since the Asymptomatic Carotid Atherosclerosis Study (ACAS) Clinical Advisory (dated September 28, 1994). Methods - Patients undergoing CEA (ICD-9-CM 38.12) in nonfederal Florida hospitals were identified from the discharge database. Data were analyzed by federal fiscal year (FY, October 1 through September 30), comparing the years following the Advisory (FY95-FY96) to the preceding 3 years (FY92-FY94). Results - There was a 68.3% increase in the number of CEAs during FY95-FY96 (mean FY92-FY94, 7 343; mean FY95-FY96, 12 356). This exceeded increases in total hospital discharges (4.5%), surgical discharges (2.2%), and the state's population (4.7%). The increase in CEAs spanned all patient demographic groups (gender, race, and age), although the magnitude was not consistent (range, 57.8% increase for 55 to 64 age group; 92.9% increase for >84 age group). Concomitantly, there was a significant decrease in mortality (1.2% versus 0.8%), cardiac complication rate (ICD-9-CM 997.1, 4.1% versus 3.0%) and percentage of patients discharged >7 days postoperatively (8.9% versus 4.9%). Mean length of stay declined 28% (5.8 versus 4.1 days), and mean adjusted charges declined 7% ($19 456 versus $18 055). Although the average case was less costly, the increased volume resulted in an estimated $56 million increase in annual hospital payments. Conclusions - The dramatic increase in the number of CEAs performed in the state of Florida after release of the ACAS Clinical Advisory suggests a causal relationship and mandates further cost-effectiveness analyses.