title: Failure of patients with peripheral arterial disease to accept the recommended treatment results in worse outcomes.
abstract: BACKGROUND
  Strategies available to facilitate decision making for patients with peripheral arterial disease (PAD) include a Markov-based decision analysis (DA) model and the Lower Extremity Grading System (LEGS) score. Both have suggested inferior outcomes when the actual treatment received (ATX) differs from that predicted. This study focuses on patient outcomes when such discordance exists.
  
  
  METHODS
  All patients referred for symptomatic lower extremity PAD over a 3-year period were evaluated using the DA model and the LEGS score. Calculated quality of life (cQOL) values were assigned before treatment based on patient symptom, perfusion, and amputation status and at follow-up (range 1.000 [perfect health] to .000 [death]). The primary outcome of cQOL was compared according to whether the ATX matched that proposed by the surgeon or predicted by the DA model or LEGS score. Secondary outcomes for revascularized patients included major adverse limb event with perioperative death (MALE + POD) and amputation-free survival (AFS).
  
  
  RESULTS
  Among 375 procedures in 345 consecutive patients, the greatest improvement in cQOL at last follow-up (median 16 months) was observed with endovascular (0.23 ± 0.16, n = 93) or open (0.21 ± 0.17, n = 137) revascularization compared with primary amputation (0.10 ± 0.07, n = 23) or medical therapy (0.04 ± 0.09, n = 122). Multivariate regression showed discordance with the surgeon's recommendation (P < 0.05) and/or the DA model (P < 0.05) to be independent predictors of improvement failure. ATX did not always agree with that proposed by the surgeon (89% agree, κ = 0.84), the DA model (68% agree, κ = 0.53), or the LEGS score (53% agree, κ = 0.32). Improvement in cQOL was greatest when ATX was concordant with treatment proposed by the surgeon (0.18 vs. 0.08, P < 0.01), the DA model (0.19 vs. 0.13, P < 0.01), or the LEGS score (0.23 vs. 0.10, P < 0.01). Patient refusal to follow the surgeon's recommendations and continued smoking were associated with minimal improvement (cQOL ranges 0.05-0.07 and 0.00-0.02, respectively), while pursuing a less morbid procedure was associated with greater improvement (cQOL range 0.28-0.38). Among revascularized patients, MALE + POD was lower at 36 months after endovascular than open surgery (21% ± 5% vs. 36% ± 4%, P < 0.05), while AFS was not significantly different. Only discordance with the surgeon's recommendation was an independent predictor of MALE + POD, possibly because of limitations in sample subset size.
  
  
  CONCLUSIONS
  Mean cQOL improved most with direct revascularization, especially when the treatment received matched that predicted by the models or proposed by the surgeon. Type of treatment received was an independent predictor of agreement of treatment with recommendations. Patient refusal to follow the recommended treatment as well as the strategy not to revascularize claudicants who persist in smoking were associated with much less patient benefit from treatment.
authors.affiliation: Ralph H. Johnson Department of Veterans Affairs Medical Center, Medical University of South Carolina, Charleston, SC. Electronic address: brothete@musc.edu.
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Brothers
mesh_terms: D000368:Aged; D000671:Amputation, Surgical; D001291:Attitude of Health Personnel; D016009:Chi-Square Distribution; D003661:Decision Support Techniques; D018450:Disease Progression; D018572:Disease-Free Survival; D005260:Female; D007722:Health Knowledge, Attitudes, Practice; D006801:Humans; D053208:Kaplan-Meier Estimate; D016015:Logistic Models; D035002:Lower Extremity / Q000098:blood supply*; D008297:Male; D008390:Markov Chains; D008875:Middle Aged; D015999:Multivariate Analysis; D010349:Patient Compliance; D018579:Patient Selection; D010361:Patients / Q000523:psychology*; D058729:Peripheral Arterial Disease / Q000175:diagnosis / Q000401:mortality / Q000523:psychology / Q000628:therapy*; D011788:Quality of Life; D012017:Referral and Consultation; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D016540:Smoking Cessation; D000074606:Smoking Prevention; D066231:Surgeons / Q000523:psychology*; D013997:Time Factors; D016896:Treatment Outcome