The obesity paradox in patients undergoing transcatheter aortic valve implantation

Abstract

Background: Obesity is a major risk factor for cardiovascular morbidity and mortality. A considerable number of studies, however, showed better outcomes for overweight patients undergoing cardiovascular interventions-the so called obesity paradox. Hypothesis: Increased body mass index (BMI) is independently associated with improved survival following transcatheter aortic valve implantation (TAVI). Methods: We analyzed the data of 409 consecutive patients undergoing TAVI in our medical center. Patients were categorized into 4 groups according to BMI: underweight (≤18.4 kg/m2 ), normal weight (18.5-24.9 kg/m2 ), overweight (25-29.9 kg/m2 ), and obese (>30 kg/m2 ). Procedure-related complications were recorded, as well as 30-day and 1-year all-cause mortality rates. Results: Obese patients had a higher prevalence of comorbidities and higher incidence of vascular complications compared with the normal-weight patients (16% vs 7%, P = 0.013). Nevertheless, 30-day mortality was similar among the groups, whereas 1-year mortality was lower among the overweight and obese patients (BMI >25) (P = 0.038). After adjusting for differences in baseline characteristics, increase in BMI was found to be independently associated with improved survival following TAVI (hazard ratio: 0.94, confidence interval: 0.89-0.99, P = 0.043). Conclusions: In our single-center study, obesity and overweight were independently associated with better outcome, supporting the obesity paradox in the TAVI population.