Race and gender affect outcomes of lower extremity bypass

Abstract

Race and gender have individually been associated with affecting outcomes in vascular interventions. We hypothesized that race and gender stratification would identify variations in outcomes of lower extremity bypass (LEB) procedures. LEB procedures were identified using Current Procedural Terminology (American Medical Association, Chicago, Ill) codes from the 2011 American College of Surgeons National Surgical Quality Improvement Program database. Individuals of races other than black or white were excluded because of small sample size. Preoperative variables, such as age, demographics, medical comorbidities, and laboratory values, were evaluated across race and gender groups using χ(2), the Student t-test, and least square means testing. Significant predictors were entered into a multivariate logistic regression model. Six primary outcomes were evaluated: major complications, minor complications, 30-day mortality, early graft failure, readmission, and length of stay (LOS). There were 4518 LEB procedures performed on black (n= 839; male [BM], 56.5%; female [BF], 43.5%) or white (n= 3679; male [WM], 66.4%; female [WF], 33.6%) patients. Black patients were more likely to be younger, diabetic, smokers, functionally dependent, dialysis dependent, and have hypertension, critical limb ischemia, higher creatinine, lower hematocrits, and higher platelet counts. Multivariate analysis revealed no statistically significant gender differences within the white cohort with respect to complications, death, graft failure, or readmission rates. WF and BM had longer LOS than WM (reference group; 4.7± 1.9days and 5.4± 2.0days vs 4.3± 2.0days, respectively; P< .006 and P< .0001) after LEB procedures, but outcomes among these groups did not differ significantly. BF had a longer LOSthan WM (5.8± 2.0days vs 4.3± 2.0days; P< .0001) and trended toward higher readmission rates (odds ratio, 1.28; 95% confidence interval, 0.97-1.70; P= .08). BF had a higher risk of early graft failure than WM (odds ratio, 2.90; 95% confidence interval, 1.52-5.49; P= .001). BF had higher early graft failure and LOS compared with WM. WF and BM also had increased LOS compared with WM. Race-gender stratification may predict outcomes in patients undergoing LEB procedures that may not be predicted by gender or race alone. Further studies using this stratification methodology may provide better insight into optimal therapeutic strategies and preventative measures for these patient subgroups. Investigation into causes of increased LOS in black patients and increased graft failure in BF may help improve outcomes.