Racial and ethnic disparities in outcomes and appropriateness of carotid endarterectomy: Impact of patient and provider factors

Background and Purpose - Prior work documented racial and ethnic disparities in incidence of stroke, stroke risk factors, and use of carotid endarterectomy. Less is known about disparities in outcomes and appropriateness of carotid endarterectomy or reasons for such inequalities. Methods - This was a population-based cohort of carotid endarterectomy performed in Medicare beneficiaries in New York. Clinical data were abstracted from medical charts to assess sociodemographics, clinical indication for carotid endarterectomy, disease severity, comorbidities, and deaths and strokes within 30 days of surgery. Appropriateness was based on validated criteria from a national expert panel. Differences in patients, providers, outcomes, and appropriateness were compared using x ² tests. Differences in risk-adjusted rates of death or nonfatal stroke were compared using multiple logistic regression accounting for patient, physician, and hospital-level risk factors. Results - Overall, 95.3% of patients undergoing carotid endarterectomy were white, 2.5% black, and 2.2% Hispanic (N=9093). Minorities had more severe neurological disease and more comorbidities and were more likely to be cared for by lower-volume surgeons and hospitals (P<0.0001). Rates of 30-day death/stroke were higher in Hispanics (9.5%) and blacks (6.9%) than whites (3.8%; P<0.0001). Multivariable analyses that adjusted for presurgical patient risk and provider characteristics found that blacks no longer had significantly worse outcomes (OR=1.37; CI, 0.78 to 2.40), although the higher risk of death/stroke in Hispanics persisted (OR= 1.87; CI, 1.09 to 3.19). Minorities had higher rates of inappropriate surgery (Hispanics 17.6%, black 13.0%, white 7.9%; P<0.0001) largely due to higher comorbidity. Conclusions - Minorities had worse outcomes and higher rates of inappropriate surgery. Differences in underlying presurgical risk factors and provider characteristics explained the higher risk of complications in blacks, but not Hispanics.