Impact of Provider Characteristics on Outcomes of Carotid Endarterectomy for Asymptomatic Carotid Stenosis in New York State.

BACKGROUND

The purpose of this study is to explore the impact of surgeon characteristics (including annual volume, specialty, and years in practice) on outcomes of carotid endarterectomy (CEA) for asymptomatic carotid atherosclerosis in New York State.

METHODS

The New York Statewide Planning and Cooperation System database was utilized to identify patients undergoing CEA from 2004 to 2011. Provider characteristics were determined by linkage to the New York Office of Professions and National Provider Identification databases. Provider-level factors were characterized by defining 5 quintiles of equal size for each factor. Hierarchical logistic regression models were created to evaluate the impact of provider characteristics on outcome.

RESULTS

In total, 36,495 patients underwent CEA for asymptomatic disease performed by vascular (75.7%), general (16.1%), cardiac (6%), and neuro (2.1%) surgeons. Outcomes of interest included in-hospital mortality (0.26%), stroke (0.45%), and the composite end point of mortality, stroke, or cardiac complication (2.2%). Unadjusted outcomes improved with increasing surgeon annual CEA volume. Mid-career surgeons had lower mortality and stroke rates than early or late-career surgeons. Odds of mortality were increased when surgery was performed by the lowest volume providers (quintile 1; 0-11 CEA/year) (odds ratio [OR] 2.62, 95% confidence interval [CI] 1.3-5.28) or a nonspecialty trained (general) surgeon (OR 1.64, 95% 1.01-2.67). After adjustment for all patient-level factors, provider volume remained an independent predictor of outcome, with significantly increased odds of mortality for volume quintile 1 (OR 2.57, 95% CI 1.27-5.23) and quintile 2 (12-22 CEA/year) (0.30%; OR 2.07, 95% CI 1-4.27) surgeons.

CONCLUSIONS

Adverse events after CEA for asymptomatic disease are comparatively rare. However, surgeon characteristics impact outcome, with the best results offered by high-volume, mid-career, specialty-trained surgeons. Efforts to define the optimal treatment of asymptomatic carotid atherosclerosis must account for the impact of surgeon characteristics on patient outcomes.