title: Enhancements to angioplasty for peripheral arterial occlusive disease: systematic review, cost-effectiveness assessment and expected value of information analysis.
abstract: BACKGROUND
  There have been rapid technological developments aimed at improving short- and long-term results of percutaneous transluminal balloon angioplasty (PTA) in peripheral arterial occlusive disease (PAD).
  
  
  OBJECTIVE
  To assess current clinical effectiveness and cost-effectiveness evidence of additional techniques to standard PTA for PAD, develop a health economic model to assess cost-effectiveness and to identify where further research is needed.
  
  
  METHODS
  Relevant electronic databases, including MEDLINE, EMBASE and The Cochrane Library were searched from inception to 2011, between May and October 2011.
  
  
  METHODS
  Systematic reviews were conducted of clinical effectiveness and cost-effectiveness. The population was participants with symptomatic PAD undergoing endovascular treatment for disease distal to the inguinal ligament. Interventions were modifications of and adjuncts to PTA in the peripheral circulation, compared with conventional PTA. Outcomes included measures of clinical effectiveness and costs. Data were extracted from randomised controlled trials (RCTs), which were quality assessed using standard criteria. Where appropriate, meta-analyses using fixed- and random-effects methods produced relative risks (RRs). A discrete-event simulation model was developed to assess the relative cost-effectiveness of the interventions from a NHS perspective over a lifetime. The patient populations of intermittent claudication (IC) and critical limb ischaemia (CLI) were modelled separately. Univariate and probabilistic sensitivity analyses were undertaken.
  
  
  RESULTS
  In total, 40 RCTs were included, many of which had small sample sizes. Significantly reduced restenosis rates were shown in meta-analyses of self-expanding stents (SES) {RR 0.67 [95% confidence interval (CI) 0.52 to 0.87]}, endovascular brachytherapy (EVBT) [RR 0.63 (95% CI 0.48 to 0.83)] at 12 months and drug-coated balloons (DCBs) at 6 months [RR 0.40 (95% CI 0.23 to 0.69)], and single studies of stent-graft or drug-eluting stent (DES), compared with PTA; a single study showed improvements with DES versus bare-metal stents (BMSs). Compared with PTA, walking capacity was not significantly affected by cutting balloon, balloon-expandable stents or EVBT; in SES, there was evidence of improvement in walking capacity after up to 12 months. The use of DCBs dominated both the assumed standard practice of PTA with bailout BMS and all other interventions because it lowered lifetime costs and improved quality of life (QoL). These results were seen for both patient populations (IC and CLI). Sensitivity analyses showed that the results were robust to different assumptions about the clinical benefits attributable to the interventions, suggesting that the use of DCBs is cost-saving.
  
  
  CONCLUSIONS
  Differing definitions of restenosis made direct comparison across trials difficult. There were few data available for walking capacity and QoL.
  
  
  CONCLUSIONS
  The evidence showed a significant benefit to reducing restenosis rates for self-expanding and DESs, stent-graft, EVBT and DCBs. If it is assumed that patency translates into beneficial long-term clinical outcomes, then DCB and bail-out DES are most likely to be the cost-effective enhancements to PTA. A RCT comparing current recommended practice (PTA with bail-out BMS) with DCB and bail-out DES could assess long-term follow-up and cost-effectiveness. Data relating patency status to the need for reintervention and to the probability of symptoms returning should be collected, as should health-related QoL measures [European Quality of Life-5 Dimensions (EQ-5D) and maximum walking distance].
  
  
  BACKGROUND
  This study is registered as PROSPERO CRD42012002014.
  
  
  BACKGROUND
  The National Institute for Health Research Health Technology Assessment programme.
authors: The University of Sheffield, School of Health and Related Research (ScHARR), Sheffield, UK.
authors: Emma L
authors: EL
authors: Simpson
authors: The University of Sheffield, School of Health and Related Research (ScHARR), Sheffield, UK.
authors: Benjamin
authors: B
authors: Kearns
authors: The University of Sheffield, School of Health and Related Research (ScHARR), Sheffield, UK.
authors: Matthew D
authors: MD
authors: Stevenson
authors: The University of Sheffield, School of Health and Related Research (ScHARR), Sheffield, UK.
authors: Anna J
authors: AJ
authors: Cantrell
authors: The University of Sheffield, School of Health and Related Research (ScHARR), Sheffield, UK.
authors: Chris
authors: C
authors: Littlewood
authors: The University of Sheffield, School of Health and Related Research (ScHARR), Sheffield, UK.
authors: Jonathan A
authors: JA
authors: Michaels
mesh_terms: D000800:Angioplasty, Balloon / Q000191:economics / Q000379:methods*; D001157:Arterial Occlusive Diseases / Q000191:economics / Q000628:therapy*; D003362:Cost-Benefit Analysis; D006801:Humans; D018803:Models, Economic; D016896:Treatment Outcome