Association of body mass index with outcomes after thoracic endovascular aortic repair in the vascular quality initiative

Objective: Although several studies have evaluated the impact of obesity on outcomes after abdominal aortic aneurysm repair, literature examining this association in thoracic endovascular aortic repair (TEVAR) is sparse. Here, we use a multiinstitutional, international database to assess the role of body mass index (BMI) on adverse outcomes in patients who underwent TEVAR for descending thoracic aortic aneurysms (DTAA) and type B dissections (TBD). Methods: A retrospective review of all patients who underwent TEVAR for DTAA or TBD from August 2014 to August 2020 was performed. Patients who were underweight (BMI <18.5 kg/m(2)) or obese (BMI$30 kg/m(2)) were compared with those of normal weight ($18.5 to <30 kg/m(2)). Adjustment for confounding was done with multivariable logistic regression or Cox proportional hazards regression as appropriate for studying postoperative or 1-year outcomes. Primary outcomes were 30day and 1-year mortality. Other outcomes included any postoperative complication, stroke, and spinal cord ischemia. Results: A total of 3423 participants were included in the study, of whom 3.3% (n = 113) were underweight, 65.9% (n = 2253) had normal weight, and 30.8% (n = 1053) were obese. Compared with normal weight, there was no significant difference in 30-day mortality in underweight patients (odds ratio [OR], 1.81; 95% confidence interval [CI], 0.80-4.14; P = .156). Obese patients who underwent TEVAR for TBD had a 2.7-fold increase in the odds of 30-day mortality compared with normal weight (OR, 2.67; 95% CI, 1.52-4.68; P = .001). Obese and normal weight patients with DTAA had equivalent odds of 30-day mortality (OR, 1.32; 95% CI, 0.79-2.23; P = .292). The adjusted hazard of 1-year mortality was 2-fold higher in underweight patients compared with normal weight (hazard ratio, 2.15; 95% CI, 1.41-3.29; P <.001), driven by a higher risk of mortality among patients with thoracic aortic aneurysm (OR, 2.62; 95% CI, 1.63-4.21; P <.001). There was no significant difference in 1-year mortality risk between normal weight and obesity in both DTAA (OR, 0.77; 95% CI, 0.54-1.09; P = .146) and TBD (OR, 1.26; 95% CI, 0.85-1.86; P = .248). Conclusions: In this study, obese patients who underwent TEVAR for DTAA had comparable 30-day and 1-year mortality risk as normal weight individuals. Obese patients who underwent TEVAR for TBD demonstrated a 2.7-fold increase in the odds of 30-day mortality, but equivalent mortality risk as normal weight patients at 1 year. TEVAR represents a safe minimally invasive option for treatment of DTAA in obese patients. Future work should be directed toward minimizing perioperative mortality among patients with TBD to optimize TEVAR outcomes.

Automated summary

This study examined the impact of body mass index (BMI) on adverse outcomes in patients who underwent TEVAR for descending thoracic aortic aneurysms (DTAA) and type B dissections (TBD). The findings suggest that underweight patients have a higher risk of mortality, while obese patients have comparable mortality risk to normal weight individuals.