Association Between Underweight Body Mass Index and In-Hospital Outcome in Patients Undergoing Endovascular Interventions for Peripheral Artery Disease: A Propensity Score Matching Analysis

Purpose: To investigate in-hospital outcomes after endovascular therapy (EVT) in patients with severe peripheral artery disease (PAD) who had a low body mass index (BMI, kg/m(2)) compared to those with normal BMI. Materials and Methods: Using weighted data from the National Inpatient Sample (NIS) database between 2002 and 2014 and ICD-9 codes, 2614 patients were identified who were aged 18 years and underwent EVT for PAD in the lower limb vessels. EVT was defined as angioplasty, atherectomy, and/or stenting. After excluding individuals with BMI >24, there were 807 (31%) normal-weight (BMI 19-24) patients and 1807 (69%) underweight (BMI <19) individuals. All patients in both groups were matched for baseline demographic and clinical characteristics and critical limb ischemia in a 1:1 propensity score matching analysis using the nearest neighbor method. Results: Propensity score matching produced 2 groups of 685 patients that differed only in the incidence of chronic lung disease, which was more frequent in low-BMI patients (p=0.04). Patients with low BMI had a higher incidence of in-hospital mortality (4.8% vs 1.2%, p<0.001), major adverse cardiovascular events (composite of death, myocardial infarction, or stroke) (7.9% vs 4.1%, p=0.003), open bypass surgery (9.1% vs 6.0%, p=0.03), and infection (14.6% vs 10.5%, p=0.02) compared with the normal-BMI group. There was no significant difference in the incidence of vascular complications (p=0.31), major bleeding (p=0.17), major amputation (p=0.35), or acute kidney injury (p=0.09) between the low- and normal-BMI groups. Conclusion: Low-BMI patients with PAD have worse in-hospital survival and more adverse outcomes after EVT.