Reduced primary patency rate in diabetic patients after percutaneous intervention results from more frequent presentation with limb-threatening ischemia.

OBJECTIVE: Although patients with diabetes are at increased risk of amputation from peripheral vascular disease, excellent limb-salvage rates have been achieved with aggressive surgical revascularization. It is less clear whether patients with diabetes will fare as well as nondiabetics after undergoing percutaneous lower extremity revascularization, a modality which is becoming increasingly utilized for this disease process. This study aimed to assess differential outcomes in between diabetics and nondiabetics in lower extremity percutaneous interventions.
METHODS: We retrospectively studied 291 patients with respect to patient variables, complications, and outcomes for percutaneous interventions performed for peripheral occlusive disease between 2002 and 2005. Tibial vessel run-off was assessed by angiography. Patency (assessed arterial duplex) was expressed by Kaplan-Meier method and log-rank analysis. Mean follow-up was 11.6 months (range 1 to 56 months).
RESULTS: A total of 385 interventions for peripheral occlusive disease with claudication (52.2%), rest pain (16.4%), or tissue loss (31.4%) were analyzed, including 336 primary interventions and 49 reinterventions (mean patient age 73.9 years, 50.8% male). Comorbidities included diabetes mellitus (57.2%), chronic renal insufficiency (18.4%), hemodialysis (3.8%), hypertension (81.9%), hypercholesterolemia (57%), coronary artery disease (58%), tobacco use (63.2%). Diabetics were significantly more likely to be female (55.3% vs 40.8%), and suffer from CRI (23.5% vs 12.0%), a history of myocardial infarction (36.5% vs 18.0%), and <three-vessel tibial outflow (83.5% vs 71.8%), compared with nondiabetics, although all other comorbidities and lesion characteristics were equivalent between these groups. Overall primary patency (+/- SE) at 6, 12, and 18 months was 85 +/- 2%, 63 +/- 3% and 56 +/- 4%, respectively. Patients with diabetes suffered reduced primary patency at 1 year compared with nondiabetics. For nondiabetics, primary patency was 88 +/- 2%, 71 +/- 4%, and 58 +/- 4% at 6, 12, and 18 months, while for diabetics it was 82 +/- 2%, 53 +/- 4%, and 49 +/- 4%, respectively (P = .05). Overall secondary patency at 6, 12, and 18 months was 88 +/- 2%, 76 +/- 3%, and 69 +/- 3%, and did not vary by diabetes status. One-year limb salvage rate was 88.3% for patients with limb-threatening ischemia, which was also similar between diabetics and nondiabetics. While univariate analysis revealed that female gender, <three-vessel tibial outflow, and a history of tobacco use were all predictive of reduced primary patency (P < .05), none of these factors significantly impacted secondary patency or limb-salvage rate. Furthermore, only limb-threatening ischemia remained a significant predictor of outcome on multivariate analysis, suggesting that the poorer primary patency in diabetics is related primarily to their propensity to present with limb-threatening disease compared with nondiabetics.
CONCLUSION: Patients with diabetes demonstrate reduced primary patency rates after percutaneous treatment of lower extremity occlusive disease, most likely due to their advanced stage of disease at presentation. However, despite a higher reintervention rate, diabetics and others with risk factors predictive of reduced primary patency can attain equivalent short-term secondary patency and limb-salvage rates. Therefore, these patient characteristics should not be considered contraindications to endovascular therapy.