Comparing Major Adverse Limb Events in Claudicants with Complete, Partial, and Non-Adherence to Pre-Operative Guideline-Directed Care.

Abstract

The Society for Vascular Surgery recommends surgery be reserved for claudicants with severe lifestyle limiting symptoms despite optimal medical therapy (OMT) and supervised exercise therapy - the sum of these known as guideline-directed care (GDC). However, most claudicants do not receive the full spectrum of GDC prior to open surgery or endovascular intervention. We investigate the impact of complete versus partial versus non-adherence to pre-operative GDC in claudicants and assess its impact on two-year major adverse limb events (MALE). A retrospective analysis was performed on claudicants with open surgery or endovascular intervention at a tertiary care institution between 2016-2023. GDC was measured prior to surgery and defined as: 1) severe lifestyle limitation documentation, 2) OMT adherence (composite of single antiplatelet agent, lipid-lowering therapy, smoking cessation), and 3) exercise therapy completion. Partial adherence was defined by meeting one or two of these components, and non-adherence was defined by meeting none of the components. The primary outcome was two-year MALE, defined as a composite of major amputation or major open/endovascular reintervention of the target limb. Statistical analysis included one-way analysis of variance, Pearson χ2 tests, Kaplan-Meier, and univariable and multivariable Cox regression modeling. Of the 258 claudicants receiving open surgery or endovascular intervention, 13.9% demonstrated non-adherence to GDC, 73.3% demonstrated partial adherence and 12.8% demonstrated complete adherence. MALE was seen in 23.3% of claudicants at two years, primarily due to re-interventions. On Kaplan-Meier analysis, claudicants with non-adherence to GDC demonstrated a two-year MALE-free survival of 66.6%, partial-adherence with 76.7%, and complete with 87.9% (p < 0.01). On multivariable Cox regression modeling, patients with complete guideline adherence demonstrated a decreased risk of MALE (hazard ratio [HR]: 0.24 [0.09, 0.69]) when compared to non-adherence, whereas partial adherence did not (0.99 [0.56, 1.74]. Complete adherence to pre-operative GDC is protective against MALE in claudicants undergoing intervention out to two years post-intervention whereas partial adherence may not offer a similar benefit. Future studies must prioritize improving adherence rates prior to surgery in claudicants to ensuring long-term risk mitigation and preventing complications.