350. Acuity and Outcomes of Coronary Artery Bypass Grafting in the United States Is Greatly Impacted by Insurance Status
Alexander Iribarne1, *Vinay Badhwar2, Maria V. Grau-Sepulveda3, *Jeffrey P. Jacobs4, Ying Xian3, *Vinod H. Thourani5, Jock N. McCullough1
1Dartmouth-Hitchcock Medical Center, Lebanon, NH;2West Virginia University, Morgantown, WV;3Duke Clinical Research Institute, Durham, NC;4The Johns Hopkins All Children’s Heart Institute, Saint Petersburg, FL;5Medstar Heart and Vascular Institute, Washington, DC
Invited Discussant: Dawn Hui
Objective: The goal of this analysis was to examine the influence of insurance status on acuity of presentation and outcomes following CABG in the United States.
Methods: This analysis included 746,161 patients from 1,169 centers undergoing first-time, isolated CABG between 2011-2016 in the Society of Thoracic Surgeons database. Patients were assigned to 1 of 7 exclusive hierarchical insurance status categories: private, private insurance plus Medicare, Medicare, Medicaid, Medicare plus Medicaid, other insurance, or none/self-pay. Logistic regression with generalized estimating equations was used to evaluate the association of insurance status with acuity of presentation, morbidity, and mortality. Risk adjustment was performed using the 2008 validated STS risk model for CABG and stratified by age group (< 65 and ≥ 65 years-old).
Results: Among patients < 65 years-old, the three most common forms of insurance were: private 61.5% (n=213,934), none 10.5% (n=36,393), and Medicaid 8.6% (n=29,779), whereas among patients ≥ 65, the most common forms were: private with Medicare 56% (n=224,313), Medicare alone 26% (n=104,851), and private alone 10.7% (n=42,774). For both age groups, there was a significant association between insurance status and acuity of presentation (p<0.0001). Patients who lacked insurance were more likely to present for CABG urgently or emergently, with a myocardial infarction within 7 days, and in congestive heart failure or cardiogenic shock. For both age groups, there was also a significant association between insurance status and risk-adjusted morbidity (a composite of permanent stroke, prolonged ventilation, renal failure, deep sternal wound infection and reoperation for cardiac reasons) and risk-adjusted operative mortality (p<0.0001). When compared to private insurance, all other forms of insurance were associated with a higher risk of operative mortality. For patients < 65, the highest odds of death were among Medicare (OR: 1.53, 1.37-1.71, p<0.0001) and Medicare + Medicaid patients (OR: 1.54, 1.34-1.76, p<0.0001). For patients ≥ 65, the highest odds of death were among those with no insurance (OR: 1.50, 1.18-1.91, p=0.001) or other insurance (OR: 1.38, 1.13-1.68, p=0.002). Among states that expanded Medicaid in 2014, there was a temporal trend toward reduced morbidity and mortality (Figure). Compared to patients from states with no Medicaid expansion, patients from states with Medicaid expansion had significantly lower risk-adjusted operative mortality whether they were < 65 (OR: 0.73, 0.66-0.81, p,0.001) or ≥ 65 years-old (OR 0.78, 0.72-0.85, p<0.0001).
Conclusions: In this large national cohort of patients undergoing isolated CABG, we demonstrate that insurance status is significantly associated with acuity of presentation as well as morbidity and mortality. Medicaid expansion was associated with a significant decrease in operative mortality.