Percutaneous Stenting of Incidental Unilateral Renal Artery Stenosis: Decision Analysis of Costs and Benefits

Abstract

Purpose: To determine the incremental cost-effectiveness of prophylactic percutaneous transluminal angioplasty with stent placement (PTA-S) in patients with incidentally discovered, asymptomatic renal artery stenosis (RAS) compared to delaying PTA-S until patients develop refractory hypertension or renal insufficiency (therapeutic PTA-S). Methods: The Markov decision analysis model was used to determine the incremental cost per quality adjusted life year (QALY) saved for prophylactic PTA-S as compared to therapeutic PTA-S in a hypothetical cohort of patients with 50% unilateral atherosclerotic RAS followed from age 61 to death. Results: Prophylactic PTA-S compared to therapeutic PTA-S results in more QALYs/patient (10.9 versus 10.3) at higher lifetime costs ($23,664 versus $16,558). The incremental cost effectiveness of prophylactic PTA-S was estimated to be $12,466/QALY. Prophylactic stenting was not cost effective (>$50,000/QALY) if the modeled incidence of stent restenosis exceeded 15%/year and the incidence of progression in the contralateral renal artery was <2% of arteries/year. Conclusions: PTA-S of incidental, asymptomatic unilateral RAS may improve patients' quality of life at an acceptable incremental cost. However, this technology should be used hesitantly until a randomized comparison confirms its effectiveness.