Prescription Trends During Lower Extremity Peripheral Artery Endovascular Interventions: Insights from the XPLAD Registry

Despite peripheral arterial intervention procedures (PAI) becoming the most utilized treatment in the symptomatic peripheral artery disease patient population, adherence to guideline management therapy (GMT) has not been well described. PAIs (n=1532) registered in the Excellence in Peripheral Artery Disease (XLPAD) registry (NCT01904851) from 13 U.S. centers between 2005 and 2013 were evaluated for adherence to GMT at discharge post-PAI, which is comprised of antiplatelet therapy (APT), lipid-lowering therapy (LLT), and renin-angiotensin pathway inhibitors (RAI) including angiotensin receptor blockers (ARB) and angiotensin converting enzyme inhibitors (ACEI). In addition, a subset of patients (n=365) were tracked over a three year period and adherence to GMT and adverse events were analyzed in SAS using a Cox proportional hazard ratio adjusted for baseline characteristics. Analysis of 1532 PAI in the study periods (n=55 in 2005-2007, n=314 in 2008-2010, and n=1,163 in 2011-2013) demonstrates an exponential rise in PAIs, consistent with national U.S. trends. This rise in PAI was not accompanied with an equally robust adherence to GMT. Excluding the limited number of patients enrolled from 2005-2007, the period between 2008 and 2013 demonstrates suboptimal adherence to GMT across all therapy groups. APT prescriptions fell from 90% to 77%, between 2008-2010 and 2011-2013 (p<0.001), and dual-APT prescriptions remained consistently low during the periods (53% vs. 48%). Consistent with the overall trend of falling adherence to GMT between 2008-2010 and 2011-2013 (55% vs. 42%; p<0.001), individual prescriptions of LLT and RAI were also significantly lower (83% vs. 66% for LLT; p<0.001 and 62% vs. 49% for RAI; p<0.001), respectively. Analysis of prescription therapy course in a subset (n=365) patients over time showed a statistically significant drops in APT (95.9% vs. 83.8%; p<0.0001) and dual-APT (74.8% vs. 31.1%; p<0.0001) therapy at one year post-PAI and a significant decrease in dual-APT therapy between one and two years post-PAI (31.1% vs. 18.9%; p=.001) (Figure 3). Cox proportional analysis in these patients showed that APT and dual-APT prescription both significantly decreased the risk of Major Adverse Cardiovascular Events (MACE) but had little effect on Major Adverse Limb Events (MALE) (Figures 1 & 2).