Trends in the national outcomes and costs for claudication and limb threatening ischemia: Angioplasty vs bypass graft

Abstract

Debate exists as to the benefit of angioplasty vs bypass graft in the treatment of lower extremity peripheral vascular disease. The associated costs are poorly defined in the literature. We sought to determine national estimates for the costs, utilization, and outcomes of angioplasty and bypass graft for the treatment of both claudication and limb threat. We searched the Nationwide Inpatient Sample (NIS) database (1999-2007), identifying patients who had an identifiable International Classification of Disease (ICD)-9 diagnosis code of atherosclerotic disease (claudication [440.21] or limb threat [440.22-440.24]). Of these, only patients who underwent intervention of angioplasty ± stent (percutaneous transluminal angioplasty [PTA; 39.50-39.90]), peripheral bypass graft (BPG; 39.29) or aortofemoral bypass (ABF; 39.25) were included. We compared demographics, costs, and comorbidities, as well as multivariable-adjusted outcomes of in-hospital mortality and major amputation. Additionally, we used the New Jersey State Inpatient and Ambulatory databases in order to better understand the influence of outpatient procedures on current volume and trends. There were 563,143 patients identified (PTA: 38%, BPG: 50%, ABF: 6%; 5.1%: multiple procedure codes). Patients who had PTA and BPG were similar in age (70.4 vs 69.5 years) but older than patients who had ABF (61.8 years, P < .01). Patients who underwent PTA were more often women (PTA: 46%, BPG: 42%, ABF: 45.2%; P < .01). Average costs for PTA increased over 60% for claudication between 2001 and 2007 ($8670 to $14,084) and limb threat ($13,903 to $23,196). For BPG, average costs increased 36% for both claudication ($9322 to $12,681) and limb threat ($16,795 to $22,910). In 2007, the average cost per procedure of PTA was higher than BPG for both claudication ($13,903 vs $12,681; P = .02) and limb threat ($23,196 vs $22,910; P = .04). The number of patients per year undergoing PTA increased threefold (15,903 to 46,138) for claudication and limb threat (6752 to 19,468). For BPG, procedures per year decreased approximately 40% for both claudication (13,625 to 9108) and limb threat (25,575 to 13,762). In-hospital mortality was similar for PTA and BPG groups for claudication (0.1% vs 0.2%; P = .04) and limb threat (2.1% vs 2.6%; P < .01). In-hospital amputation rates were significantly higher for patients who had PTA (7%) than BPG (3.9%, odds ratio [OR], 1.67 [1.49-1.85]; P < .01) or patients who underwent ABF (3.0%; OR, 2.32 [1.79, 3.03]; P < .01). PTA has altered the treatment paradigm for lower limb ischemia with an increase in costs and procedures. It is unclear if this represents an increase in patients or number of treatments per patient. Although mortality is slightly lower with PTA for all indications, amputation rates for limb-threat patients appear higher, as does the average cost. Longitudinal studies are necessary to determine the appropriateness of PTA in both claudication and limb-threat patients. The mortality benefit with PTA may be ultimately lost, and average costs elevated, if multiple interventions are performed on the same patients.