Fewer Complications in the Obese Following Lower Extremity Endovascular Interventions

Abstract

Background: The prevalence of obesity is increasing in the United States; however, its impact on adverse outcomes in patients with peripheral vascular disease is not well studied. Obesity is associated with higher rates of complications following open bypass surgery, but limited data are available on its effect on endovascular intervention. This study aimed to identify whether obese patients suffer the same complications when undergoing lower extremity endovascular interventions.

Methods: All patients who underwent femoropopliteal or tibial endovascular interventions between 2011 and 2013 were identified in the Targeted Vascular Module of the National Surgical Quality Improvement Program. Patients were stratified into 5 groups based on their body mass index (BMI): underweight (<18.6), normal weight (18.6-24.9), overweight (25-29.9), obese (30-34.9), and morbidly obese (≥35). Those patients without a documented BMI or a defined target lesion were excluded. Baseline demographics, patient characteristics, operative details, and outcomes were compared using univariate analysis between the BMI groups. Multivariable logistic regression was used to account for patient demographics and operative details.

Results: 3,246 patients underwent endovascular interventions (78% femoropopliteal and 22% tibial). Of these, 137 (4%) were underweight, 881 (27%) were normal weight, 1,193 (37%) were overweight, 647 (20%) were obese, and 388 (12%) were morbidly obese. There were no differences in 30-day mortality; however, surgical site infection (SSI) was higher in the morbidly obese (5% vs. normal weight: 2%, P = 0.02), whereas untreated patency loss was lower (morbidly obese: 0.5%, obese: 1%, normal weight: 2%, P = 0.02). Other important 30-day outcomes, including bleeding and amputation, were similar across the BMI groups. Following multivariate analysis, SSI remained more common in the morbidly obese (odds ratio [OR]: 2.6, 95% confidence interval [CI]: 1.4-5.0), whereas untreated patency loss remained lower in both overweight and morbidly obese patients (overweight: OR 0.5, 95% CI: 0.2-0.9 and morbidly obese: OR: 0.2, 95% CI: 0.05-0.85). Length of stay >1 day was significantly lower in the overweight, obese, and morbidly obese (OR 0.7, 95% CI: 0.6-0.8; OR 0.6, 95% CI: 0.5-0.7; and OR 0.7, 95% CI: 0.5-0.9, respectively).

Conclusions: Few major complications occur in the obese in the first 30 days following endovascular interventions, and obesity is not an independent predictor of 30-day mortality. Rates of postoperative SSIs are low overall, although they are highest in morbidly obese patients (5%, compared to 2% in normal weight patients). Given this knowledge, endovascular interventions are a prudent treatment option for this patient population.