Predictors of amputation and survival following lower extremity revascularization in hemodialysis patients

Background. Peripheral vascular disease (PVD) has become increasingly common in end-stage renal disease (ESRD) patients, leading to an increase in the rate of revascularization and amputation. We studied the prognosis of ESRD patients undergoing their first revascularization procedure. Methods. We conducted a longitudinal cohort study of hemodialysis patients enrolled in special studies of the United States Renal Data System. Cox proportional hazards analysis was used to assess the independent effect of type of initial revascularization procedure on lower extremity amputation and all-cause, cardiac, and infectious mortality over 3 years, after adjustment for sociodemographic, clinical, and biologic baseline characteristics. Results. Eight hundred patients underwent an initial revascularization procedure by surgical bypass or angioplasty. The overall incidence of subsequent amputation was 16.3/100 person-years, 22.6 for bypass, and 5.7 for angioplasty. After adjustment for patient characteristics, the risk of amputation was higher for bypass versus angioplasty [relative hazard (RH) 4.00; 95% CI 2.46 to 6.57], for black versus white patients (RH 1.49; 95% CI 1.04 to 2.15), for uninsured or patients on Medicaid versus patients with private insurance or on Medicare (RH 1.65; 95% CI 1.12 to 2.72), and for patients with diabetes versus no diabetes (RH 2.51; 95% CI 1.67 to 3.76). Compared with patients who underwent angioplasty, the risk of all-cause (RH 1.37; 95% CI 1.10 to 1.70), cardiac (RH 1.50; 95% CI 1.08 to 2.09), and infectious (RH 2.17; 95% CI 1.10 to 4.29) mortality was greater among patients who underwent bypass. Conclusion. Risk of amputation following revascularization procedures was positively associated with type of procedure, black race, uninsurance/Medicaid, and diabetes status. Risk of death was also higher following bypass. While this might reflect underlying severity of disease, patient education, screening, and optimal care of lower extremities should be emphasized to detect PVD at an early stage of the disease process.