Outcomes following first-time lower extremity revascularization between patients with and without diabetes

Abstract

OBJECTIVES: Data on the effect of diabetes type (insulin-dependent vs. noninsulin- dependent) on short- and long-term outcomes after lower extremity revascularization for chronic limb-threatening ischemia (CLTI) are lacking. We sought to address this paucity of information by evaluating outcomes in patients with insulin-dependent and noninsulin-dependent diabetes after first-time bypass and endovascular interventions. METHODS: We reviewed all limbs undergoing a first-time infrainguinal bypass (BPG) or percutaneous transluminal angioplasty with or without stent (PTA/S) for CLTI at our institution from 2005-2014. Based on preoperative medication regimen, patients were categorized as having insulin-dependent diabetes (IDDM), noninsulin-dependent diabetes (NIDDM), or no diabetes (NDM). Outcomes included wound healing, major amputation, RAS events (revascularization, major amputation, or stenosis), major adverse limb events (MALE), and mortality. Outcomes were evaluated using Chi-square, Kaplan-Meier, and Cox regression analyses. RESULTS: Of 2,869 infrainguinal revascularizations from 2005-2014, 1,294 limbs (646 BPG, 648 PTA/S) fit our criteria and underwent a first-time revascularization for CLTI. Overall, 703 IDDM, 262 NIDDM, and 329 NDM limbs were included in our analysis. IDDM patients, compared to NIDDM and NDM, were younger (69 vs. 73 vs. 77 years; P<.001) and more often presented with tissue loss (89% vs. 77% vs. 67%; P<.001), coronary artery disease (57% vs. 48% vs. 43% P<.001), and end-stage renal disease (26% vs. 13% vs. 12%; P<.001). Perioperative complications, including mortality (3% vs. 2% vs. 5%; P=.07), did not differ between the three groups; however, complete wound healing at 6-month follow-up was significantly worse among IDDM patients (36% vs. 40% vs. 51%; P<.001). Irrespective of intervention type, IDDM patients had significantly higher three-year major amputation rates (BPG: 24% vs. 16% vs. 10%, P=.04; PTA/S: 21% vs. 6% vs. 5%, P<.001). Multivariable analyses illustrated that, compared to NDM, IDDM was associated with significantly higher risk of both major amputation and RAS events following any first-time intervention (Hazard Ratio (HR) 2.5, 95% Confidence Interval [CI] 1.2-5.2 and 1.4 [1.1-1.9], respectively). Similar associations were found for a PTA/S-first intervention (3.1 [1.1-9.0] and 1.5 [1.1-2.2], respectively), while IDDM patients undergoing a BPG-first intervention were only associated with incomplete wound healing (1.5 [1.3-2.9]). Lastly, when compared to NDM, NIDDM was associated with lower late mortality (0.6 [0.5-0.8]). CONCLUSIONS: As compared to NDM, IDDM was associated with similar perioperative and long-term mortality but a higher risk of incomplete wound healing, major amputation, and future RAS events, especially after a PTA/S-first approach. Interestingly, NIDDM was associated with lower long-term mortality and not associated with any adverse limb events. Overall, these data demonstrate both the importance in distinguishing between diabetes types, as well as potential long-term benefit of a bypass-first strategy in appropriately selected IDDM patients with CLTI.