Original Investigation
August 2016

Efficacy of a Guideline-Recommended Risk-Reduction Program to Improve Cardiovascular and Limb Outcomes in Patients With Peripheral Arterial Disease

Author Affiliations
  • 1Division of Vascular Surgery, St Michael’s Hospital, Toronto, Ontario, Canada
  • 2Department of Surgery, University of Toronto, Toronto, Ontario, Canada
  • 3Li Ka Shing Knowledge Institute, St Michael’s Hospital, Toronto, Ontario, Canada
  • 4King Saud University–Li Ka Shing Collaborative Research Program
  • 5Department of Surgery, King Saud University, Riyadh, Saudi Arabia
  • 6Institute of Health Policy, Management, and Evaluation, University of Toronto, Toronto, Ontario, Canada
  • 7Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario, Canada
  • 8Applied Health Research Centre, Toronto, Ontario, Canada
  • 9Institute for Clinical Evaluative Sciences, Toronto, Ontario, Canada
  • 10Division of Vascular Surgery, Peter Munk Cardiac Centre, University Health Network, Toronto, Ontario, Canada
  • 11Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada
  • 12Division of Cardiac Surgery, St Michael’s Hospital, Toronto, Ontario, Canada

Copyright 2016 American Medical Association. All Rights Reserved. Applicable FARS/DFARS Restrictions Apply to Government Use.

JAMA Surg. 2016;151(8):742-750. doi:10.1001/jamasurg.2016.0415

Importance  Patients with peripheral arterial disease (PAD) are at a high risk for cardiovascular events, yet, to our knowledge, no studies have examined the effect of a comprehensive risk-reduction program on long-term outcomes for patients with PAD.

Objective  To investigative whether a program that focuses on 8 major guideline-recommended risk-management therapies reduces cardiovascular and limb events in patients with PAD.

Design, Setting and Participants  An observational cohort study with up to 7 years of follow-up was conducted using data from administrative databases from Ontario, Canada, between July 1, 2004, and March 31, 2013. Patients with symptomatic PAD who were enrolled in the Systematic Assessment of Vascular Risk (SAVR) program at a single tertiary vascular center in Ontario between July 2004 and April 2007 were matched with up to 2 (control) patients with PAD from other Ontario tertiary vascular centers not enrolled in the program using propensity score methods. Cox proportional hazards regression analysis was used to compare outcomes.

Exposures  Program that promoted antiplatelet agents, statins, angiotensin-converting enzyme inhibitors, blood pressure control, lipid control, diabetic glycemic control, smoking cessation, and target body mass index by engaging vascular surgeons, family physicians, and patients with PAD.

Main Outcomes and Measures  The primary outcome was a composite risk ratio of death, acute myocardial infarction, or ischemic stroke. Secondary outcomes included rates of lower limb amputations, bypass surgical procedures, and peripheral angioplasties with and without a stent.

Results  A total of 791 patients were studied after propensity score matching; the mean (SD) age of patients in the SAVR group (n = 290) was 67.9 (10.4) years and 68.2 (11.2) years in the control group (n = 501). During follow-up, the SAVR group experienced the primary outcome at a significantly lower rate than the control group (adjusted hazard ratio [HR], 0.63; 95% CI, 0.52-0.77). Patients in the SAVR group were also less likely to have major amputation (adjusted HR, 0.47; 95% CI, 0.29-0.77), minor amputation (adjusted HR, 0.26; 95% CI, 0.13-0.54), bypass surgery (adjusted HR, 0.47; 95% CI, 0.30-0.73), or hospitalization due to heart failure (adjusted HR, 0.73; 95% CI, 0.53-1.00). The rate of peripheral angioplasty with or without a stent was higher among the SAVR group (adjusted HR, 2.97; 95% CI, 2.15-4.10).

Conclusions and Relevance  A guideline-recommended risk-reduction program targeted at patients with PAD was associated with fewer cardiovascular and limb events over the long-term. This finding emphasizes the need for well-designed prospective studies to develop and examine the effect of such programs on reducing PAD-related morbidity, mortality, and health care costs.